COM111 Introduction to Computer Applications Essential Computer Concepts Part II

Networks and the Internet Why do users access the Internet? 2.Information 3.Shopping 4.Banking and Investing 5.Classes 6.Entertainment 1.Communications 7.Download Music 8.Share Information

Networks and the Internet What is the Web? A Web site is a collection of related Web pages A Web page contains text, graphics, audio, video, and links to other Web pages You can share information on a social networking Web site or a photo sharing community  Billions of documents, called Web pages, available to anyone connected to the Internet A blog consists of time- stamped articles in a journal format A podcast is recorded audio stored on a Web site that can be downloaded

Consists of a series of instructions that tells the computer what to do and how to do it Computer Software What is software? Also called a program

Computer Software What is a graphical user interface (GUI)?  Allows you to interact with the software using text, graphics, and visual images such as icons  Controls how you enter data and instructions and how the screen displays information

Computer Software What is system software? Operating System (OS) Operating System (OS) is a set of programs that coordinates all activities among computer hardware devices Utility Programs Utility Programs allow the user to perform maintenance-type tasks usually related to managing a computer, its devices or its programs  Programs that control or maintain the operations of the computer and its devices

Computer Software What is application software? Presentation Graphics Spreadsheet Database Word Processing  Programs designed to make users more productive

Computer Software How do you install and run programs? Step 1: INSTALL When you insert a greeting card program disc in the CD drive for the first time, the computer begins the procedure of installing the greeting card program on the hard disk. Step 2: RUN Once installed, you can instruct the computer to run the greeting card program. The computer transfers instructions from the hard disk to memory. Step 3: USE The greeting card program executes. Using this program, you can create custom greeting cards.

Computer Software What is a programmer?  Someone who develops application or system software  Programmer writes the instructions to direct the computer to process data into information JavaScript Web application

Categories of Computers What are the categories of computers? Personal Computers (desktop) Mobile Computers and Mobile Devices Game Consoles Servers Mainframes Supercomputers Embedded Computers

11 Classification of Computers Personal Computers Notebook Computers Handheld Computers Midrange Computers Mainframes Supercomputers Servers Embedded – Special Purpose Computers

12 Personal Computers Desktop computers  Also known as PCs, microcomputers, or home computers Broken down into three categories:  Low-end computers  Fully-powered personal computers  Workstations Network computer  Central processing unit and minimal memory  Designed to be used on a network  Sometimes called the client

13 PC Categories Low-end computers  Fine for home users, word processing, simple games, Internet access Fully powered computers  Good for heavy use of graphics, programming, or action-oriented games Workstations  Very high-end computers used by engineers, financial traders, and graphic designers

14 Computer Types  Personal computer :  A small, single-user computer based on a microprocessor. Different personal computer types with different OS: PC/MAC/Workstation  Minicomputer :  A multi-user computer capable of supporting from 10 to hundreds of users simultaneously.  Mainframe :  A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously. Dumb terminal interface  Supercomputer :  An extremely fast computer that can perform hundreds of millions of instructions per second. The Big Blue series of supercomputers is designed and programmed to try to beat human grand masters at chess

Personal Computers What are the two most popular styles of personal computers?  PC and compatibles use the Windows operating system  Apple Macintosh usually uses the Macintosh operating system (Mac OS X)

Personal Computers What is a desktop computer?  Designed so all of the components fit entirely on or under a desk or table

17 Personal Computer  Other companies adjusted to IBM's dominance by building IBM clones, computers that were internally almost the same as the IBM PC, but that cost less. Because IBM clones used the same microprocessors as IBM PCs, they were capable of running the same software. Over the years, IBM has lost much of its influence in directing the evolution of PCs.  Today, the world of personal computers is basically divided between Apple Macintoshes and PCs. The principal characteristics of personal computers are that they are single-user systems and are based on microprocessors. However, although personal computers are designed as single-user systems, it is common to link them together to form a network. In terms of power, there is great variety. At the high end, the distinction between personal computers and workstations has faded. High-end models of the Macintosh and PC offer the same computing power and graphics capability as low-end workstations by Sun Microsystems, Hewlett-Packard.

18 Personal Computer  A small, relatively inexpensive computer designed for an individual user. In price, personal computers range anywhere from a few hundred dollars to thousands of dollars. All are based on the microprocessor technology that enables manufacturers to put an entire CPU on one chip. Businesses use personal computers for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At home, the most popular use for personal computers is for playing games.

19 Personal Computer  Personal computers first appeared in the late 1970s. One of the first and most popular personal computers was the Apple II, introduced in 1977 by Apple Computer. During the late 1970s and early 1980s, new models and competing operating systems seemed to appear daily. Then, in 1981, IBM entered its first personal computer, known as the IBM PC. The IBM PC quickly became the personal computer of choice, and most other personal computer manufacturers fell by the wayside. One of the few companies to survive was Apple Computer, which remains a major player in the personal computer marketplace.

20 Workstation  A type of computer used for engineering applications (CAD), desktop publishing, software development, and other types of applications that require a moderate amount of computing power and relatively high quality graphics capabilities.  Workstations generally come with a large, high-resolution graphics screen, at least 64 MB (megabytes) of RAM, built- in network support, and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive. The most common operating systems for workstations are UNIX and Windows NT.

21 Workstation  In terms of computing power, workstations lie between personal computers and minicomputers, although the line is fuzzy on both ends. High-end personal computers are equivalent to low-end workstations. And high-end workstations are equivalent to minicomputers.  Like personal computers, most workstations are single-user computers. However, workstations are typically linked together to form a local-area network, although they can also be used as stand-alone systems.  In networking, workstation refers to any computer connected to a local-area network. It could be a workstation or a personal computer.

22 Midrange Computers Multi-user computers designed to serve the needs of medium-sized organizations  Hundreds or thousands of users connected  Used for order-entry, and other company-wide applications

23 Mainframe  The chief difference between a supercomputer and a mainframe is that a supercomputer channels all its power into executing a few programs as fast as possible, whereas a mainframe uses its power to execute many programs concurrently.

24 Mainframe  A very large and expensive computer capable of supporting hundreds, or even thousands, of users simultaneously. In the hierarchy that starts with a simple microprocessor (in watches, for example) at the bottom and moves to supercomputers at the top, mainframes are just below supercomputers. In some ways, mainframes are more powerful than supercomputers because they support more simultaneous programs. But supercomputers can execute a single program faster than a mainframe.

25 Supercomputer  The fastest type of computer. Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, fluid dynamic calculations, nuclear energy research, and petroleum exploration.