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Information & Communication Technology (ICT) Health Sciences Lecture 1: Introduction to computer 2 Objectives Differentiates laptop, tablet and server Describe the relationship between data and information Brie...

Information & Communication Technology (ICT) Health Sciences Lecture 1: Introduction to computer 2 Objectives Differentiates laptop, tablet and server Describe the relationship between data and information Briefly explain the various of input option 3 What is the role of technology in your life? Where do you use it? 4 Digital literacy involves having a current knowledge and understanding of computer,mobile devices, Internet and related technologies 5 Computer A computer is an electronic device, operating under the control of instructions stored in its own memory that can accept data (input), process the data according to specified rule produce information (output), and store the information for future use 6 What is hardware? What is software? What is server? Watch youtube https://www.youtube.com/watch? v=yMDVGUYWz8U 7 Functionalities of a computer. Any digital computer carries out five functions in gross terms: 1. Take data as input 2. Store the data/instructions in its memory and use when they required 3. Processes the data and convert it into something useful 4. Generate the output 5. Coordinate all the above 8 Computer Components Any kind of computers consists of HARDWARE AND SOFTWARE. Hardware: Computer hardware is the collection of physical elements that constitutes a computer system. Computer hardware refers to the physical parts or components of a computer such as the monitor, mouse, keyboard, computer data storage, system unit (graphic cards, sound cards, memory, motherboard and chips), etc. all of which are physical objects that can be touched 9  The Motherboard The motherboard, sometimes called a system board, is the main circuit board of the computer. On personal computers, the circuitry for the processor, memory, and other components reside on a computer chip(s). A computer chip is a small piece of semiconducting material, usually silicon, on which integrated circuits are etched. An integrated circuit contains many microscopic pathways capable of carrying electrical current. Each integrated circuit can contain millions of elements such as resistors, capacitors, and transistors. A transistor, for example, can act as an electronic switch that opens or closes the circuit for electrical charges.  Processors The processor, also called the central processing unit (CPU), interprets and carries out the basic instructions that operate a computer. On larger computers, such as mainframes and supercomputers, the various functions performed by the processor extend over many separate chips and often multiple circuit boards. On a personal computer, all functions of the processor usually are on a single chip. Some computer and chip manufacturers use the term microprocessor to refer to a personal computer processor chip. A multi-core processor is a single chip with two or more separate processor cores. Multi-core processors are used in all sizes of computers Processors contain a control unit and an arithmetic logic unit (ALU). When a user runs an application, for example, its instructions transfer from a storage device to memory. Data needed by programs and applications enters memory from either an input device or a storage device. The control unit interprets and executes instructions in memory, and the arithmetic logic unit performs calculations on the data in memory. Resulting information is stored in memory, from which it can be sent to an output device or a storage device for future access, as needed The arithmetic logic unit (ALU), another component of the processor, performs arithmetic,comparison, and other operations. Arithmetic operations include basic calculations, such as addition, subtraction, multiplication, anddivision. Comparison operations involve comparing one data item with another to determine whether the first item is greater than, equal to, or less than the other item. Depending on the result of the comparison, different actions may occur.  Machine Cycle For every instruction, a processor repeats a set of four basic operations, which comprise a machine cycle: (1) fetching, (2) decoding, (3) executing, and, if necessary, (4) storing. Fetching is the process of obtaining a program or an application instruction or data item from memory. Decoding refers to the process of translating the instruction into signals the computer can execute. Executing is the process of carrying out the commands. Storing, in this context, means writing the result to memory (not to a storage medium)  Registers A processor contains small, high-speed storage locations, called registers, that temporarily hold data and instructions. Registers are part of the processor, not part of memory or a permanent storage device. Processors have many different types of registers, each with a specific storage function. Register functions include storing the location from where an instruction was fetched, storing an instruction while the control unit Personal Computer and Mobile Device Processors The leading manufacturers of personal computer processor chips are Intel and AMD. AMD manufactures Intel-compatible processors, which have an internal design similar to Intel processors,perform the same functions, and can be as powerful, but often are less expensive. These manufacturers often identify their processor chips by a model name or model number  Processor Cooling Processor chips for laptops, desktops, and servers can generate quite a bit of heat, which could cause the chip to malfunction or fail. Some computer cases locate additional fans near certain components, such as a processor, to provide additional cooling. Heat sinks, liquid cooling technologies, and cooling mats often are used to help further dissipate processor heat. A heat sink is a small ceramic or metal component with fins on its surface that absorbs and disperses heat produced by electrical components, such as a processor. Many heat sinks have fans to help distribute air dissipated by the heat sink. Some heat sinks are packaged as part of a processor chip. Some computers use liquid cooling technology to reduce the temperature of a processor. Liquid cooling technology uses a continuous flow of fluid(s), such as water and glycol, in a process that transfers the heated fluid away from the processor to a radiator-type grill, which cools the liquid, and then returns the cooled fluid to the processor. Laptop users often use a cooling pad to help further reduce the heat generated by their computer. A cooling pad rests below a laptop and protects the computer from overheating and also the user’s lap from excessive heat. Some cooling pads contain a small fan to transfer heat away from the laptop. These types of cooling pads often draw power from a USB port. Instead of using power, other pads absorb heat through a conductive material inside the pad.  Memory Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data (information). Memory usually consists of one or more chips on the motherboard or some other circuit board in the computer. Memory stores three basic categories of items: 1. The operating system and other programs that control or maintain the computer and its devices 2. Applications that carry out a specific task, such as word processing 3. The data being processed by the applications and the resulting information This role of memory to store both data and programs is known as the stored program concept.  The following sections discuss these types of memory. RAM RAM (random access memory), also called main memory, consists of memory chips that can be read from and written to by the processor and other devices. When you turn on power to a computer or mobile device, certain operating system files (such as the files that determine how the desktop or home screen appears) load into RAM from a storage device such as a hard drive. These files remain in RAM as long as the computer or mobile device has continuous power. As additional applications and data are requested, they also load into RAM from storage. The processor interprets and executes a program or application’s instructions while the program or application is in RAM. During this time, the contents of RAM may change. RAM can accommodate multiple programs and applications simultaneously. Most RAM is volatile, which means it loses its contents when the power is removed from the computer. For this reason, you must save any data, instructions, and information you may need in the future. Saving is the process of copying data, instructions, and information from RAM to a storage device such as a hard drive. Cache Most of today’s computers improve their processing times with cache (pronounced cash),which is a temporary storage area. Two common types of cache are memory cache and disk cache. Memory cache helps speed the processes of the computer because it stores frequently used instructions and data.  Adapters Although the circuitry in many of today’s computers integrates all the necessary functionality, some require additional capabilities in the form of adapters. Desktops and servers use adapter cards; mobile computers use USB adapters. Adapter Cards An adapter card, sometimes called an expansion card or adapter board, is a circuit board that enhances the functions of a component of a desktop or server system unit and/or provides connections to peripheral devices. An expansion slot is a socket on a desktop or server motherboard that can hold an adapter card. Two popular adapter cards are sound cards and video cards. Software Software is a generic term for organized collections of computer data and instructions, often broken into two major categories: system software that provides the basic non-task-specific functions of the computer, and application software which is used by users to accomplish specific tasks. 28 Data and Information Data: Facts and figures which relay something specific, but which are not organized in any way and which provide no further information regarding patterns, context, etc. So data means "unstructured facts and figures that have the least impact on the typical manager." Information: For data to become information, it must be contextualized, categorized, calculated and condensed. Information thus paints a bigger picture; it is data with relevance and purpose. It may convey a trend in the environment, or perhaps indicate a pattern of sales for a given period of time. Essentially information is found "in answers to questions that begin with such words as who, what, where, when, and how many 29 30 Task Find the specification of your own gadget including your laptop, tablet or personal computer. 31 32