Lecture 2 Computers and Digital Basics (2).pdf

BCS101- Computer Science Fundamentals Fall 2024 / 2025 Lec 2: Computers and Digital Basics Dr. Esraa Mosleh  Agenda All Things Digital ❖ Digital Revolution Convergence Digital Devices ❖Computer Basics ❖ Input and Output Devices...

BCS101- Computer Science Fundamentals Fall 2024 / 2025 Lec 2: Computers and Digital Basics Dr. Esraa Mosleh  Agenda All Things Digital ❖ Digital Revolution Convergence Digital Devices ❖Computer Basics ❖ Input and Output Devices ❖ Motherboard 2  The Digital Revolution What is the digital revolution? The digital revolution is an ongoing process of social, political, and economic change brought about by digital technology, such as computers and the Internet. The digital revolution became a significant factor in the 1980s, as computers and other digital devices became popular and as the Internet opened global communications. The term digital revolution was probably coined as a parallel to the term industrial revolution, and in that sense it promises to bring about a similar level of social and economic change. 3  The Digital Revolution (cont.) What technologies are fueling the digital revolution? The digital revolution revolves around a constellation of technologies, including digital electronics, computers, communications networks, the Web, and digitization. What’s the significance of digital electronics? Digital electronics use electronic circuits to represent data. In the 1940s and 1950s, engineers began to develop digital electronic devices and refine the electronic components used to build them. Transistors and then integrated circuits, which we call computer chips, were key factors in making electronic devices increasingly smaller and less expensive (Figure 1-1). 4 The Digital Revolution (cont.) FIGURE 1 Digital devices, such as this wireless mouse 5  The Digital Revolution (cont.) Consumers first became acquainted with digital electronics through digital watches that appeared in 1972, and then with handheld electronic calculators popularized by Texas Instruments in 1973. Today, digital electronic devices include computers, portable media players such as iPods, digital cameras and camcorders, cell phones, radios and televisions, GPSs (Global Positioning Systems), DVD and CD players, e-book readers, digital voice recorders. Even cars and appliances, such as microwave ovens, refrigerators, and washing machines, include digital electronics for control, monitoring, and fault diagnosis. 6  The Digital Revolution (cont.) When did computers enter the picture? Engineers built the first digital computers during World War II. By the 1950s, a few computers were being used for business data processing applications, the first personal computers became available in 1976. What caused the sudden upswing in computer ownership? The second phase of the digital revolution materialized when the Internet was opened to public use. The Internet is a global computer network originally developed as a military project, then handed over to the National Science Foundation for research and academic use. 7  The Digital Revolution (cont.) When commercial Internet use was first allowed in 1995, companies such as AOL and CompuServe began to offer Internet access and e-mail to a quickly growing list of subscribers. E-mail, a form of electronic communication, In addition to e-mail, the Internet offers many ways for people to communicate and interact. Chat groups where people exchange typed messages in real-time remain popular today. Online social networks, such as Facebook (Figure 1-2), have become wildly popular. After completing a short questionnaire to become a member, you can choose to interact with your friends or with friends of those friends. 8  The Digital Revolution (cont.) Other social networking options include Twitter, a service for posting short text messages through the Twitter Web site or by texting. FIGURE 2 9  The Digital Revolution (cont.) The Internet allows people to share resources as well as interact. Individuals’ computers can be linked together in grid networks with powerful processing capabilities. A computer network is a group of computers linked by wired or wireless technology to share data and resources. Network technology existed before the Internet became popular, but the first computer networks were mainly deployed in schools and businesses. They were complicated to set up, unreliable, and offered only local connectivity. Network technology eventually became consumer-friendly, allowing homeowners to connect multiple computers for sharing printers, files, and an Internet connection. 10  The Digital Revolution (cont.) Wireless networks offered even more advantages. Soon Wi-Fi hotspots sprung up in airports, coffee shops, and hotels. Whereas the Internet enhanced communications, wireless network technology offered convenience and made digital information as accessible as radio stations. What about the Web? When historians look back on the digital revolution, they are certain to identify the Web as a major transformative influence. The Web (short for World Wide Web) is a collection of linked documents, graphics, and sounds that can be accessed over the Internet. 11  Digitization and Convergence What is meant by digitization? Digitization is the process of converting text, numbers, sound, photos, and video into data that can be processed by digital devices. What is convergence? Your cell phone has a camera. Your clock has a radio. Your thermometer also reports the humidity. Your PDA plays digital music. All these are examples of technological convergence, a process by which several technologies with distinct functionalities evolve to form a single product. In the pre-digital days, convergence often meant combining two technologically different devices in a single box. 12  Digital Devices Computer Basics Input and Output Devices Motherboard Machine cycle Memory vs. Storage 13  Computer Basics Computer: a programmable, electronic device that accepts data, performs operations, presents the results, and can store the data or results Input: entering data into the computer Processing: performing operations on the data Output: presenting the results Storage: saving data, programs, or output for future use 14 Information Processing Cycle 15 Basic Hardware of a Personal Computer 16  Input Devices What is an input Device? Hardware Mechanism that transforms information in the external world for consumption by a computer. Examples of input Devices: Keyboard, Mouse, Trackball, touchpad, mouse stick, Microphone, Scanner, Bar code reader, Card reader 17 Input Devices (cont.) 18 Input Devices (cont.) 19  Output Devices What is an output Device? It includes any hardware that translates information processed by the computer into a form that humans can understand. Examples of Output Devices: Monitor, Printer, Speaker, Plotter 20  Monitor A monitor is a peripheral device that displays computer output on a screen. 21  Types of Monitors Cathode-ray tube (CRT): CRT They resemble televisions, use picture tube technology, and are inexpensive, but they take up desk space and use a lot of energy. Liquid Crystal Display (LCD or flat-panel): LCD Cells sandwiched between two transparent layers form images; used for notebook computers, PDAs, cellular phones, and personal computers; expensive, and they take up less desk space and use less energy than CRT monitors. 22  Printers A printer is a peripheral device that produces a physical copy or hard copy of the computer’s output. There are two basic types of printers: ❖ Impact printer ❖ Nonimpact printer 23  Impact Printers An impact printer is a printer that has a print head that contacts the paper to produce a character. It uses ink ribbon. It is noisy, produces Near-letter quality printouts, and is not commonly used today. Dot-matrix: Pins are used to make characters. Impact printer Dot-matrix 24  Nonimpact Printers There are two types of nonimpact printers: Inkjet printer– Also called bubble-jet; makes characters by inserting dots of ink onto paper. Laser printer works like a copier; quality is determined by dots per inch (dpi) Inkjet Laser 25  Multifunction Printers A multifunction printer combines the functions of a nonimpact printer, scanner, fax machine, and copier in one unit. 26  Plotter A plotter is a printer that uses a pen that moves over a large revolving sheet of paper. It is used in engineering and map printing 27 Central Processing Unit (CPU) 28 Central Processing Unit (CPU) (cont.) 29  Motherboard It holds and allows communication between many of the electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. It is on the size of A4 paper, its color is green or gold. 30 Inside a Typical System Unit 31 32  Conclusion A computer can be defined by its ability to accept input, process data, store data, and produce output, all according to a set of instructions from a computer program. You can see the processing cycle in action when you use your digital textbook. 33 Thanks for your kind listening