Module-1-CC-101.pdf

CC 101 – Introduction to Computing Module in CC 101 – Introduction to Computing Prepared by: HERNAN B. DE HONOR, EdD...

CC 101 – Introduction to Computing Module in CC 101 – Introduction to Computing Prepared by: HERNAN B. DE HONOR, EdD Associate Professor V Disclaimer/Non-disclosure: “This material is distributed for the students of Aklan State University for academic purposes only. Reproduction of this material without the consent of the University is strictly prohibited.” AKLAN STATE UNIVERSITY-College of Industrial Technology 1 CC 101 – Introduction to Computing WHAT ARE COMPUTERS? Computers are programmable electronic devices that can store, retrieve and process data. Data are collections of facts (Input) while information are collections of processed data (Output). They are capable of interpreting and executing program commands for input/output computation and logic operation. It stores the information that can be retrieved at anytime for future use. It can process huge amounts of data at a fast speed. It can do the same task repeatedly with no mistakes. However, a computer cannot think for itself. It is dependent on the instructions you will give to it. These instructions will then be followed by the computer. THE EVOLUTION OF COMPUTERS Human fingers are known to be the simplest and earliest computing device. Pebbles and stones as well as markings scratched on rocks were also used to do simple computing. Abacus This device allows users to make computations using a system of sliding beads arranged on a rack. Early merchants used the abacus in conducting their business transactions. Difference Machine In 1822, Charles Babbage, a British Mathematics professor, invented the Difference Engine. Powered by steam and as large as a locomotive, the machine had the capacity to perform calculations and print the results. AKLAN STATE UNIVERSITY-College of Industrial Technology 2 CC 101 – Introduction to Computing Analytical Engine In 1833, several years after Babbage worked on the Difference Engine, he began working on the first general- purpose digital computer, which he called the ANALYTICAL ENGINE. It was intended to use loops of Jacquard's punched cards to control an automatic calculator, which could make decisions based on the results of previous computations. This machine was also intended to employ several features subsequently used in modern computers, including sequential control, branching, and looping. ENIAC Between 1943 and 1946, the ENIAC or the Electronic Numerical Integrator and Computer was developed by John Presper Eckert and John Mauchly, was the first large-scale, electronic, digital computer capable of being reprogrammed to solve a full range of computing problems, although earlier computers had been built with some of these properties. ENIAC was designed and built to calculate artillery firing tables for the U.S. Army’s Ballistics Research Laboratory. EDVAC Electronic Discrete Variable Automatic Computer was one of the earliest electronic computers. Unlike its predecessor the ENIAC, it was binary rather than decimal, and was a stored program computer. ENIAC inventors John Mauchly and J. Presper Eckert proposed the EDVAC's construction in August 1944. A contract to build the new computer was signed in April 1946 with an initial budget of US$100,000. EDVAC was delivered to the Ballistics Research Laboratory in August 1949. The computer had almost 6,000 vacuum tubes and 12,000 diodes, and consumed 56 kW of power. It covered 490 ft² (45.5 m²) of floor space and weighed 17,300 lb (7,850 kg). The full complement of operating personnel was thirty people per eight-hour shift. AKLAN STATE UNIVERSITY-College of Industrial Technology 3 CC 101 – Introduction to Computing UNIVAC 1 In 1948, the UNIVAC or the Universal Automatic Computer was manufactured by Remington Rand Corporation. This became one of the first commercially available computers to benefit from the various advances in computing. IBM 360 The IBM 360 is introduced in April of 1964 and quickly becomes the standard institutional mainframe computer. On early computers, program control was still partially under manual control. Much debugging could also take place. Programs could be stopped, execution could be stepped instruction by instruction, or program control is switched to other memory locations and restarted there. The contents of all registers, any memory cell, and the status of input-output channels could be displayed by the operator. ALTAIR 8800 January 1975, it is hailed as the first "personal" computer. The Altair is generally credited with launching the PC revolution. Microsoft was founded to make software (BASIC) for the Altair. APPLE II 1977: The Apple II is announced the first personal computer to come in a plastic case and include color graphics, the Apple II was an impressive machine. And with the introduction in early ‘78 of the Apple Disk II, the most inexpensive, easy to use floppy drive ever (at the time). AKLAN STATE UNIVERSITY-College of Industrial Technology 4 CC 101 – Introduction to Computing APPLE MACINTOSH The Apple Macintosh debuts in 1984. It features a simple, graphical interface, uses the 8-MHz, 32-bit Motorola 68000 CPU, and has a built-in 9-inch B/W screen. The Mac also had a floppy disk drive that used 3.5" disks, which were physically smaller than their 5.25" PC counterparts, but were sturdier and could hold more data (400k). POWER MAC FAMILY In 1994 Apple announced the PowerMac family, the first Macs to be based on the PowerPC chip, an extremely fast processor co-developed with IBM and Motorola. The PowerPC processor allowed Macs to compete with, and in many cases beat, the speed of Intel's newer processors. CLASSIFICATION OF COMPUTERS Computers are available in different shapes, sizes, and weights, due to these different shapes and sizes they perform different sorts of jobs from one another. Here we are going to introduce different classifications of computers. 1. Supercomputer An extremely fast computer that can perform hundreds of millions of instructions per second. Governments use this type of computer for their different calculations and heavy jobs. In most of the Hollywood's movies it is used for animation purposes. This kind of computer is also helpful for forecasting weather reports worldwide. AKLAN STATE UNIVERSITY-College of Industrial Technology 5 CC 101 – Introduction to Computing 2. Mainframe Computer A giant computer after the Supercomputer, which can also process millions of instruction per second and capable of accessing billions of data. This computer is commonly used in big hospitals, airline reservations companies, and many other huge companies. 3. Minicomputer A multi-user computer capable of supporting from 10 to hundreds of users simultaneously. This computer is next in line but offers less than mainframe in work and performance. These are the computers, which are mostly preferred by the small type of business, colleges, etc. 4. Personal Computer/Microcomputer A small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data. Laptop also called notebook, laptops are portable computers that integrate the display, keyboard, a pointing device or trackball, processor, memory and hard drive all in a battery-operated package slightly larger than an average hardcover book. The approach for this computer is also the same as the personal computer. It can store the same amount of data having a memory of the same size as that of a personal computer. MAIN COMPONENTS OF A COMPUTER SYSTEM A computer system consists of hardware, software, and peopleware. These components go hand in hand in enabling computers to function accordingly and support your various needs and wants. Without any one of these components, the computer system will not operate. AKLAN STATE UNIVERSITY-College of Industrial Technology 6 CC 101 – Introduction to Computing 1. HARDWARE The term hardware refers to the physical components of your computer. These are the parts that you can touch and see. Input and output devices, the computer’s memory and the CPU are examples of hardware. 2. SOFTWARE Software is a set of programs that control the operations of the computer system. Computer programs are sets of instructions that instruct the computer on what to do and what to perform. a. System Software is a computer program that assists your computer to function well. An Operating system, such as Microsoft Windows 7, is an example of System Software. b. Application Software is a computer program that performs a specific task. Examples of application software include so software used in word processing, spreadsheet, computer presentations, graphics and multimedia and entertainment. Programming Languages A programming language is a standardized communication technique for expressing instructions to a computer. Like human languages, each language has its own syntax and grammar. Programming languages enable a programmer to precisely specify what data a computer will act upon, how these data will be stored/transmitted, and precisely what actions to take under various circumstances. Types of Programming Languages: 1. Machine Language The computer’s native language, which differs among different types of computers, is its machine language – a set of built-in primitive instructions. These instructions are in the form of binary code, so in telling the machine what AKLAN STATE UNIVERSITY-College of Industrial Technology 7 CC 101 – Introduction to Computing to do, you have to enter binary code. 2. Assembly language Assembly language is a low-level programming language in which a mnemonic is used to represent each of the machine language instructions. Assembly languages were developed to make programming easy. However, since the computer cannot understand assembly language, a program called the assembler is used to convert assembly language programs into machine code. Assembly language is machine dependent; an assembly program can be executed only on a particular kind of machine. 3. High-Level Languages High-level languages are developed to overcome the platform specific problem of assembly language and make programming easier. High-level languages are English-like and easy to learn and program. There are over one hundred high-level languages. The well-known ones are: COBOL (COmmon Business Oriented Language) FORTRAN (FORmula TRANslation) BASIC (Beginner’s All-purpose Symbolic Instruction Code) Pascal (named for Blaise Pascal) Ada (named for Ada Lovelace) C (whose developer designed B first) Visual Basic (Basic-like visual language developed by Microsoft) Delphi (Pascal-like visual language developed by Borland) C++ (an object-oriented language, based on C) C# (a Java-like language developed by Microsoft) Java A program written in a high-level language is called a source-program or source code. Since a computer cannot understand a source program, a program called a compiler is used to translate the source program into a machine language program. Operating Systems The Operating Systems (OS), the most important program that runs on a computer, enables it to manage and control its activities. Application programs, such as a Web browser or a word processor, cannot run without an operating system. AKLAN STATE UNIVERSITY-College of Industrial Technology 8 CC 101 – Introduction to Computing The major tasks of the operating system are: 1. Controlling and monitoring system activities 2. Allocating and assigning system resources 3. Scheduling operations 3. PEOPLEWARE Peopleware is the one who uses the computer system. Computer Engineers The Computer Engineers are commonly engage in software design and application to address the needs of a particular industry or sector. The Computer Engineers are primarily responsible for the update in the software as well as providing additional customization of current software to ensure the system's functionality. In addition to this, the field of robotics needs the expertise of a Computer Engineer to improve its designs and functions proficiently. Software Engineers The Software Engineer is primarily responsible for the design and development of the software of the computers, as well as its testing and evaluation. They usually work on computer chips to ensure that it is functioning well and suited to the company's needs. Information Technology Specialists The IT Specialists are tasked to plan and coordinate the installation, operation, troubleshooting and maintenance of the computer's software and hardware systems. They ensure that the necessary security programs, procedures and policies are implemented to guaranty the company's data are safe and secure. Website Designer Website designers engage in the construction of the navigation schemes of a website. Their job also includes putting together online content and applications in the internet. They also work on the web page's layout as well as the strategic placement of the useful and practical information about the website. At times, they are also responsible for conceptual design and branding. AKLAN STATE UNIVERSITY-College of Industrial Technology 9 CC 101 – Introduction to Computing Computer Technicians These technicians are in charge with the repair and maintenance of computers and its servers. They also build or configure new hardware as well as installing and bringing up to date the software. They are also tasked with the creation and maintenance of computer networks. BASIC COMPONENTS OF COMPUTER Just like human body, a computer has parts. The parts of your computer should be functioning well so that the entire computer will function well, too. 1. INPUT DEVICES Input devices are used to enter data into the computer. The keyboard and the mouse are the most common examples of input devices. a. KEYBOARD A keyboard is used to type data into your computer. It is also used to issue commands to the computer. A computer keyboard has keys for letters, numbers and symbols. It has keys that perform special functions as well as keys that will allow you to move around your screen monitor. KEYBOARD LAYOUT TYPES QWERTY KEYBOARD LAYOUT The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard because the first six keys on the top row of letters spell QWERTY. It was designed in the 1800s for mechanical typewriters and was actually designed to slow typists down to avoid jamming the keys. AKLAN STATE UNIVERSITY-College of Industrial Technology 10 CC 101 – Introduction to Computing DVORAK KEYBOARD LAYOUT The Dvorak keyboard is designed so that the middle row of keys includes the most common letters. In addition, common letter combinations are positioned in such a way that they can be typed quickly. In addition to the standard Dvorak keyboard, there are two additional Dvorak keyboards, a left-handed and right-handed keyboard. These keyboards are designed for people who have only one hand for typing. KEYBOARD CONNECTION TYPES 1. PS/2 The PS/2 connector is used for connecting, a keyboard to a PC compatible computer system. Its name comes from the IBM Personal System/2 series of personal computers, with which it was introduced in 1987. The keyboard connector replaced the larger 5-pin DIN used in the IBM PC/AT design. Universal Serial Bus (USB) Is a serial bus standard to interface devices. The connectors are designed to be robust. Many previous connector designs were fragile, with pins or other delicate components prone to bending or breaking, even with the application of only very modest force. The electrical contacts in a USB connector are protected by an adjacent plastic tongue, and the entire connecting assembly is further protected by an enclosing metal sheath. As a result USB connectors can safely be handled, inserted, and removed, even by a small child. The encasing sheath and the tough molded plug body mean that a connector can be dropped, stepped upon, even crushed or struck, all without damage; a considerable degree of force is needed to significantly damage a USB connector. AKLAN STATE UNIVERSITY-College of Industrial Technology 11 CC 101 – Introduction to Computing Cordless It uses low-powered radio waves to transmit data between devices. The term refers to communication without cables or cords, chiefly using radio frequency and infrared waves. GENERAL KEYBOARD FUNCTIONS  Caps Lock key- locks the keyboard into capital letters. When Caps Lock is on the shift key produces lower case letters.  Tab key- is usually marked by two arrows pointing in opposite directions to vertical lines, to indicate that its purpose is to indent text from the margins.  Escape key- usually marked Esc, is in the top left hand corner. If something is happening on your computer that you want to stop, try pressing this key. In most computer applications this will stop, or cancel, the operation.  Delete key- usually does what it says. Deletes whatever the cursor is on.  The keys marked Control and Alt (Alternate); and the Shift Keys can all be used in combination with other keys to give commands.  A block of Four Arrow keys is at the bottom, to the right of the typewriter pad. These keys are properly called cursor control keys. AKLAN STATE UNIVERSITY-College of Industrial Technology 12 CC 101 – Introduction to Computing  The key marked End usually moves the cursor to the end of the line.  The Space bar at the bottom generally makes spaces on the screen. But, like the other keys, it can do different things at different applications.  The large key on the right with a downwards-pointing bent arrow is one of the two Enter (or Return) keys. There is another on the far right with "Enter" written on it. Either key can be used to start a new line for what you are writing on screen or to tell the computer to carry out, an instruction you have given it.  One of the biggest differences between a typewriter keyboard and the computer keyboard is the row of keys at the top of the keyboard that are labeled F1 through F12.  F1 – If you press Fl while working in a program, help for that program will usually appear. If you press F1 while at the Windows desktop or when the Windows Explorer is open, a Windows help screen will pop up.  F2 – You can use the F2 key to rename an item when working in Windows. Highlight any folder or tile, and press F2. You will then be able to type a new name for the object.  F3 – When you are working in Windows, the F3 key will open the Find Files window.  F4 – You can use this key to open the Address bar when working in Internet Explorer. This will allow you to type the address of a Web Page for quick access. You can also press the Alt key and the F4 at the same time to close the open Window that you are currently working on. AKLAN STATE UNIVERSITY-College of Industrial Technology 13 CC 101 – Introduction to Computing  F5 –it is the refresh key. You can press F5 when viewing a Web page to make sure that you have the most current version of that web page. You can also use F5 when in Windows to refresh the screen.  F6 – This key is often used to move the cursor around the structure of the program. Pressing it will often cycle you from window to window.  F7 – The key does not have any functionality in Windows. It may, however be used in some individual programs. To find out if it is available in the program you are using, bring up the program's help screen and type in the words function key.  F8 – This key can be used to access Safe Mode if pressed during the computer’s boot up process. This is a troubleshooting mode, which will start the computer with minimal drivers.  F9 – This key does not have any functionality in Windows. It may, however be used in some individual programs. To find out if it is available in the program you are using, bring up the program's help screen and type in the words function key.  F10 – is the key that is used to activate the menu bar in many programs. You can use F10 to highlight the first menu choice, and then use the arrow keys to move around the menus. Pressing the Shift key while pressing F10 will bring up the shortcut menu. This is similar to right clicking on an object.  F11 – Press F11 when you are working in Internet Explorer and the window will open to full screen mode. This will make all toolbars disappear and can be useful to see more information on the screen. Press F11 when you are in full screen mode will toggle you back to your normal view.  F12 - This key does not have any functionality in Windows. It may, however be used in some individual programs. To find out if it is available in the program you are using, bring up the program's help screen and type in the words function key. b. MOUSE A mouse is used to execute commands by pressing a button. A mouse has the left and right buttons. As you move the mouse, a mouse pointer also moves on your screen monitor. AKLAN STATE UNIVERSITY-College of Industrial Technology 14 CC 101 – Introduction to Computing ***** Trivia: In 1964, the first prototype computer mouse was made to use with a graphical user interface (GUI), “windows”. Engelbert received a patent for the wooden shell with two metal wheels in 1970, describing it in the patent application as an “X-Y position indicator for a display system.” It was nicknamed the mouse because the tail came out the end,” Engelbert revealed about his invention. ***** TYPES OF MOUSE There are basically two different types of mice: mechanical and optical. 1. The mechanical mouse has a small hard rubber ball underneath that moves against two rollers as it is passed across a flat surface. Mechanical sensors detect the movement of the rollers as an “x” and “y” axis and the cursor on screen is moved accordingly. 2. An optical mouse is more accurate or precise and has no moving parts. It uses a laser to detect movement and has to be paired with a special pad or mat that has an embedded optical reference grid. MOUSE CONNECTION TYPES 1. The serial mouse is, by far, the most popular and the easiest to install. They connect to an RS-232C serial port; one of the COM ports on the back of the computer (a DB-9 or a DB-25 male connector). A serial port is an interface that transmits one bit at a time, and RS-232C is a standard that most serial ports conform to. 2. The PS/2 mouse seems to be the answer to both problems. It is a type of serial mouse but it connects to a PS/2 connector (female mini-DIN-6). It installs as simply as any serial mouse, does not use up a COM port, and needs no expansion card installed. AKLAN STATE UNIVERSITY-College of Industrial Technology 15 CC 101 – Introduction to Computing 3. A cordless mouse uses infrared technology to do away with the cord. It seems like it would be a good idea because the cord on a mouse can be a real pain. It drags across the top of the desk, gets caught and hangs up in the other cords, or anything that might be lying on your desktop. They also have a receptor that must be visible to the mouse (line of sight), if anything is in the way, the mouse won't respond. 4. The USB mouse has become one of the most advanced (and one of the best) connections around for mice, printers and other peripherals. Installation is simple. It is hot swappable, so you can plug it in even when your computer is running. The mouse is immediately recognized and you can use it right away. GENERAL MOUSE FUNCTIONS: 1. Point - Point is pointing your mouse pointer over an object. 2. Click – Click is done by pressing the left button of the mouse once and then releasing it. 3. Right Click – is done by pressing the right button of the mouse once and then releasing it. 4. Double click – is done by pressing the left button of the mouse twice in rapid succession. 5. Drag and Drop – drag is done by clicking the object and moving it while pressing the left button of the mouse and then drop is done by simply releasing the left button of the mouse. c. Joystick Joystick is also a pointing device which is used to move cursor position on a monitor screen. It is a stick having a spherical ball at its both lower and upper ends. The lower spherical ball moves in a socket. The joystick can be moved in all four directions. The function of joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing(CAD) and playing computer games. AKLAN STATE UNIVERSITY-College of Industrial Technology 16 CC 101 – Introduction to Computing d. Light Pen Light pen is a pointing device which is similar to a pen. It is used to select a displayed menu item or draw pictures on the monitor screen. It consists of a photocell and an optical system placed in a small tube. When the tip of a light pen is moved over the monitor screen and pen button is pressed, its photocell sensing element detects the screen location and sends the corresponding signal to the CPU. e. Track Ball Track ball is an input device that is mostly used in notebook or laptop computer, instead of a mouse. This is a ball which is half inserted and by moving fingers on ball, pointer can be moved. Since the whole device is not moved, a track ball requires less space than a mouse. A track ball comes in various shapes like a ball, a button and a square. f. Scanner Scanner is an input device which works more like a photocopy machine. It is used when some information is available on a paper and it is to be transferred to the hard disc of the computer for further manipulation. Scanner captures images from the source which are then converted into the digital form that can be stored on the disc. These images can be edited before they are printed. g. Microphone Microphone is an input device to input sound that is then stored in digital form. The microphone is used for various applications like adding sound to a multimedia presentation or for mixing music. AKLAN STATE UNIVERSITY-College of Industrial Technology 17 CC 101 – Introduction to Computing h. Magnetic Ink Card Reader(MICR) MICR input device is generally used in banks because of a large number of cheques to be processed every day. The bank's code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable. This reading process is called Magnetic Ink Character Recognition (MICR). The main advantages of MICR is that it is fast and less error prone. i. Optical Character Reader(OCR) OCR is an input device use d to read a printed text. OCR scans text optically character by character, converts them into a machine readable code and stores the text on the system memory. j. Bar Code Readers Bar Code Reader is a device used for reading bar coded data (data in form of light and dark lines). Bar coded data is generally used in labeling goods, numbering the books etc. It may be a hand held scanner or may be embedded in a stationary scanner. Bar Code Reader scans a bar code image, converts it into an alphanumeric value which is then fed to the computer to which bar code reader is connected. k. Optical Mark Reader(OMR) OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It is used where one out of a few alternatives is to be selected and marked. It is specially used for checking the answer sheets of examinations having multiple choice questions. AKLAN STATE UNIVERSITY-College of Industrial Technology 18 CC 101 – Introduction to Computing 2. OUTPUT DEVICES Output devices are used to display what you are doing with your computer. The monitor and the Printer are the most common examples of output devices. a. MONITOR A monitor looks like a television screen. It displays what you are currently doing in your computer. The monitor shows information on the screen when you type. This is called outputting information. TYPES OF MONITOR  Cathode Ray Tube (CRT) The CRT, or cathode ray tube, is the picture tube of your monitor. Although it is a large vacuum tube, it is shaped more like a bottle. The tube tapers near the back where there is a negatively charged cathode, or electron gun. The electron gun shoots electrons at the back of the positively charged screen, which is coated with a phosphorous chemical. This excites the phosphors causing them to glow as individual dots called pixels (picture elements). The image you see on the monitor's screen is made up of thousands of tiny dots (pixels).  Liquid Crystal Display (LCD) Is a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector. It is prized by engineers because it uses very small amounts of electric power, and is therefore suitable for use in battery-powered electronic devices. Each pixel of an LCD consists of a layer of liquid crystal molecules suspended between two transparent electrodes, and two polarizing filters, the axes of polarity of which are perpendicular to each other. Without the liquid crystals between them, light passing through one would be blocked by the other. AKLAN STATE UNIVERSITY-College of Industrial Technology 19 CC 101 – Introduction to Computing MONITOR CONNECTION TYPES 1. Analog (VGA) Connection Most CRT monitors require the signal information in analog (continuous electrical signals or waves) form and not digital (pulses equivalent to the binary digits 0 and 1), they typically use an analog connection. Once the display information is in analog form, it is sent to the monitor through a VGA cable. The cable connects at the back of the computer to an analog connector (also known as a D-Sub connector) that has 15 pins in three rows. 2. DVI Connection DVI keeps data in digital form from the computer to the monitor. There is no need to convert data from digital information to analog information. LCD monitors work in a digital mode and support the DVI format. (Although, some also accept analog information, which is then converted to digital format.) At one time, a digital signal offered better image quality compared to analog technology. However, analog signal processing technology has improved over the years and the difference in quality is now minimal. GENERAL MONITOR FUNCTIONS Power -Turns the monitor on/off. Brightness - Using this button or wheel the user can increase and decrease the brightness on the screen. Contrast - Using this button or wheel can increase and decrease the amount of contrast on the screen. Horizontal Size - Allows for the picture on the screen to be stretched to the horizontal edge of the monitor. Vertical Size - Allows the picture on the screen to be stretched to the vertical edges of the monitor. Horizontal Position - Allows the picture to move moved Horizontally, once in the center the user can then use the Horizontal size to stretch it to have an equal amount of black border on each side. AKLAN STATE UNIVERSITY-College of Industrial Technology 20 CC 101 – Introduction to Computing Vertical Position - Like the Horizontal Position, using this button or wheel the user can move the picture up or down to center the picture more appropriately. Full Screen - Sets monitor to full screen b. PRINTER A printer is used to print on paper what you have done in your computer. The printer takes the information on your screen and transfers it to paper or a hard copy. There are many different types of printers with various levels of quality. The three basic types of printer are; dot matrix, inkjet, and laser. TYPES OF PRINTER  Dot matrix printer Refers to a type of computer printer with a print head that runs back and forth on the page and prints by impact, striking an ink-soaked cloth ribbon against the paper, much like a typewriter.  Ink jet printer A computer printer that operates by propelling tiny droplets of liquid ink onto paper. This is the most common type of computer printer for the general consumer due to their low cost, high quality of output, capability of printing in vivid color, and ease of use. Work like dot matrix printers but fires a stream of ink from a cartridge directly onto the paper.  Laser printer A common type of computer printer that rapidly produces high quality text and graphics on plain paper. Like photocopiers, laser printers employ a xerographic printing process but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photoreceptor. AKLAN STATE UNIVERSITY-College of Industrial Technology 21 CC 101 – Introduction to Computing PRINTER CONNECTION TYPES 1. Parallel Connection The cable connection between the computer and another device's parallel ports, which allows a computer to send several bits of data simultaneously. 2. Serial Connection A cable that can be used to transfer information between two devices. Serial cables use the RS-232 standards for their connectors. The serial cable can be any combination of male or female in a DB9 or DB25 connector type. The original RS-232 connector was intended to be a 25-pin connector (DB25). 3. USB Connection An external bus standard that supports data transfer rates of 12 Mbps. A single USB port can be used to connect up to 127 peripheral devices. GENERAL PRINTER FUNCTIONS Dot Matrix Printers  It has the ability to handle a wide range of paper types, including continuous paper, multipart forms, labels, envelopes and postcards.  High speed of printing of up to 285 characters per second at 10 characters per inch. Ink-jet Printers  The dots can have different colors combined together to create photo- quality images. Laser Printers  Laser printer print speeds of up to 15 pages per minute. It has 150 sheets input tray and supports plain paper up to legal size, as well as envelopes, transparencies, post cards and labels. AKLAN STATE UNIVERSITY-College of Industrial Technology 22 CC 101 – Introduction to Computing  Laser print cartridge is simple to use featuring ultra precise toner and the imaging drum. Print cartridge installation & replacement is quick and convenient. c. Projector Projectors are display devices that project a computer-created image. The computer sends the image data to its video card, which then sends the video image to the projector. They are typically used for presentations or for viewing videos. d. Audio Output/Speaker Computers produce audio data that requires output devices such as speakers and headphones to deliver the sound to you. Audio data is created by the computer and then sent to the audio card, which is located in an expansion slot. The card translates the data into audio signals, which are sent to the audio output device. e. Plotter Plotters create a hard copy of a digitally rendered design. The design is sent to the plotter via a graphics card and creates the design using a pen. Generally used with engineering applications, plotters basically draw an image using a series of straight lines. CENTRAL PROCESSING UNIT (SYSTEM UNIT) The CPU or the Central processing Unit is the "brain' of the Computer. It is responsible for processing instructions and carrying out commands. AKLAN STATE UNIVERSITY-College of Industrial Technology 23 CC 101 – Introduction to Computing Motherboard Supplies all the electrical connections among various components of a computer. The motherboard is inside the CPU box. It is a circuit board that the CPU, Input/Output chips and peripheral cards plug into Microprocessor The exact term processor is a sub-system of a data processing system, which processes received information after it has been encoded into data, by the input sub-system. These data are then processed by the processing sub- system before being sent to the output sub-system where they are decoded back into information. However, in common parlance, processor is usually to the microprocessor, the brain of the modern day computers. Processor speed is measured in Megahertz (MHz), a unit of measurement used to compare the clock speeds of computers. The higher the value (eg. MHz), the quicker computer actions are processed. AKLAN STATE UNIVERSITY-College of Industrial Technology 24 CC 101 – Introduction to Computing TYPES OF PROCESSOR Budget/Value Processor Intel Celeron and AMD Sempron – is a large number of different budget x86 microprocessors produced by Intel and AMD marketed as a budget/value CPU line. It is suitable for most applications and their performance is somewhat limited when it comes to running intense applications. It was used in many low-end machines and in some ways, became the standard for non-gaming computers. Performance Processor Intel Core 2 Quad and AMD 64 Athlon X2 - designed to deliver performance across usages— such as image processing, video content creation, games and multimedia—where end-users can truly appreciate the advanced performance and multitasking capabilities. Power supply Is an electrical transformer regulates the electricity used by the computer. Random-Access Memory or RAM The RAM is the temporary storage of data and programs. RAM in a computer is considered main memory or primary storage: the working area used for loading, displaying and manipulating applications and data. AKLAN STATE UNIVERSITY-College of Industrial Technology 25 CC 101 – Introduction to Computing Memory Memory chips are normally only available as part of a card called a module. You have probably seen memory listed as 8x32 or 4x16. These numbers represent the number of the chips multiplied by the capacity of each individual chip, which is measured in megabits (Mb), or one million bits. Take the result and divide it by eight to get the number of megabytes on that module. For example, 4x32 means that the module has four 32- megabit chips. Multiply 4 by 32 and you get 128 megabits. Since we know that a byte has 8 bits, we need to divide our result of 128 by 8. Our result is 16 megabytes. TYPES OF RAM DIP 18-pin (DRAM chip, usually pre-FPRAM) SIPP (usually FPRAM) SIMM 30 -pin (usually FPRAM) SIMM 72-pin (so-called "PS/2 SIMM", usually EDO RAM) DIMM 168-pin (SDRAM) DIMM 184-pin (DDR SDRAM) AKLAN STATE UNIVERSITY-College of Industrial Technology 26 CC 101 – Introduction to Computing STORAGE MEDIA Storage media are used to store your data and programs. The floppy disk, the hard disk and the CD-ROM are the most common examples of storage media.  3 ½ FIoppy Disk A 3½ floppy disk is the most common storage medium for small amounts of data. A floppy disk can store 1.44 or 2.88 megabytes of data. You insert a floppy disk into a floppy drive to read and write data from and to the floppy disk.  Hard Disk The hard disk is the storage medium for huge amount of data. A hard disk can store several gigabytes of data. The hard disk is usually installed inside the CPU box. Almost all hard disks today are of either the 3.5" or 2.5" varieties, used in desktops and laptops, respectively. 2.5" disks are usually slower and have less capacity but use less power and are more tolerant of movement. An increasingly common size is the 1.8" disks used in portable MP3 players and subnotebooks, which have very low power consumption and are highly shock-resistant. Capacity is measured in bytes, and speed is measured by transfer rate in bytes per second and access time in milliseconds (ms). Hard disk access times range from 3ms to about 15ms, whereas CDs and DVDs range from 80ms to 120ms. AKLAN STATE UNIVERSITY-College of Industrial Technology 27 CC 101 – Introduction to Computing Hard Disk Interface Integrated Drive Electronics (IDE) -was later renamed to ATA, and then PATA. The name comes from the way early families had the hard disk controller external to the disk. Moving the hard disk controller from the interface card to the disk helped to standardize interfaces, reducing cost and complexity. The data cable was originally 40 conductors, but UDMA modes from the later disks requires using an 80 conductor cable (note that the 80 conductor cable still uses a 40 position connector.) The interface changed from 40 pins to 39 pin. The missing pin acts as a key to prevent incorrect insertion of the connector, a common cause of disk and controller damage. Serial Advance Technology Attachment (SATA) - The SATA data cable has only one data pair for the differential transmission of data to the device, and one pair for receiving, from the device. That requires that data be transmitted serially. The same differential transmission system is used in RS485, LocalTalk, USB, Firewire, and differential SCSI. In 2005/2006 parlance, the 40 pin IDE/ATA is called "PATA" or parallel ATA, which means that there are 16 bits of data transferred in parallel at a time on the data cable.  Compact disk-Read Only Memory or CD-ROM The CD-ROM is the storage medium of many computer programs. A CD-ROM can store about 640 megabytes of data. It is circular in shape. The CD-ROM is inserted into the CD-ROM drive which reads information from it. AKLAN STATE UNIVERSITY-College of Industrial Technology 28 CC 101 – Introduction to Computing Digital Versatile Disc or DVD The DVD is an optical disc storage media format that can be used for data storage, including movies with high video and sound quality. DVDs resemble compact discs as their physical dimensions are the same (120mm (4.72 inches) or occasionally 80mm (3.15 inches) in diameter) but they are encoded in a different format and at a much higher density.  USB Flash Drive USB flash drives are storage devices about the size of your thumb. They plug into the side or the back of your computer, into a socket called USB port. They can store billion bits of data. USB flash drives are compact and easy-to-use devices that are similar in use to your computer hard drive.  Secure Digital (SD) Card Is a non-volatile memory card format developed for use in portable devices. It is widely used in digital cameras, digital camcorders, handheld computers, netbook computers, PDAs, media players, mobile phones, GPS receivers, and video games. The capacity range for standard- and high-capacity (SDHC) cards overlap, beginning at 4 GB, but SDHC's upper limit had reached 32 GB as of mid- 2009. SDXC (eXtended Capacity), a specification announced at the 2009 Consumer Electronics Show, allows for up to 2 TiB cards. AKLAN STATE UNIVERSITY-College of Industrial Technology 29 CC 101 – Introduction to Computing WHAT IS A NETWORK? A computer network is simply two or more computers connected together so they can exchange information. A small network can be as simple as two computers linked together by a single cable. TYPES OF NETWORK 1. By Scale  Workgroup – is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area.  Intranet - An intranet is a private computer network that uses Internet Protocols, Network connectivity, and possibly the public telecommunication system to securely share part of an organization's information or operations with its employees. Sometimes the term refers only to the most visible service, the internal website. The same concepts and technologies of the Internet such as clients and servers running on the Internet protocol suite are used to build an intranet.  Internet – It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked web pages and other documents of the World Wide Web. 2. By Connection Method  Wi-Fi – short or wireless fidelity and is meant to be used generically when referring of any type of 802.11 network, whether 802.11b, 802.11a, dual-band, etc. The term is promulgated by the Wi-Fi Alliance. A person AKLAN STATE UNIVERSITY-College of Industrial Technology 30 CC 101 – Introduction to Computing with a Wi-Fi enabled device such as a computer, cellphone or PDS can connect to the Internet when in proximity of an access point. The region covered by one or several access points is called Hotspot.  DSL – is a family of technologies that provide digital transmission over the wires of a local telephone network. DSL originally stood for Digital Subscriber Loop, although in recent years, many have adopted Digital Subscriber Line as a more marketing- friendly term for the most popular version of DSL.  Dial-up access – is a form of data access (mainly used for Internet access) in which the client uses a modem to connect a computer to a telephone line and dials into an Internet Service Provider's (ISP) node to establish a modem-to- modem link, which is then routed to the Internet. 3. Functional Relationship  Peer-to-Peer Network - You can build a simple, small network without using the complex and expensive equipment used in large networks. On such a network, often called a peer-to-peer network, each computer can communicate with any other computer on the network.  Client-Server Network - Large networks use powerful servers to provide networking services. This type of network is often called a client-server network. The servers control network access and provide services such as file storage, network printing, and Internet access. The computers or clients on the network access the servers to log on, access files, and print documents. AKLAN STATE UNIVERSITY-College of Industrial Technology 31 CC 101 – Introduction to Computing NETWORKING HARDWARE 1. Network adapter cards Expansion cards that provide the physical connection between each computer and the network. The card that is installed into a slot on your computer, just like a sound card or modem card. Some newer computers have a network adapter already built into the system. 2. Network hub The central connection point for network cables that connect to computers or other devices on a network. The hub has several network cable jacks or ports that you use to connect network cables to computers. The hub contains circuitry that enables each computer to communicate with any other computer connected to the hub. 3. Network cables This is special, unshielded twisted-pair (UTP) cables used to connect each computer to the hub. The cable you need is Category 5 UTP cable with a square plastic RJ-45 connector on each end. What can I do with Simple Networks? Without a network, you can access resources only on your own computer. These resources may be devices in your computer, such as a folder or disk drive, or they may be connected to your computer, such as a printer or CDROM drive. These devices, accessible only to you, are local resources. Networking allows you to share resources among a group of computer users. AKLAN STATE UNIVERSITY-College of Industrial Technology 32 CC 101 – Introduction to Computing Sharing Files and Drives If your computers are connected to a network, each computer can make its resources available to other computers in your office by sharing them over the network. Each computer, on your network can share folders, entire disk drives, or a CD- ROM drive. Then other computers on your network can access documents and other files stored in the folders and on the drives. Instead of copying a document to a diskette and giving it to another person to view, anyone can open and view the document using the network. Sharing a Printer If you have a printer connected to your computer, you can share the printer with other computers on the network. Then instead of buying a printer for every computer, all the computers can print across the network to the printer. Suppose you want to print a document on a color laser printer that is connected to another computer in the office. Instead of copying your file to a disk, going to the other computer, and interrupting the person using that computer, you can print directly over the network. AKLAN STATE UNIVERSITY-College of Industrial Technology 33