1. Computers and Communication

2. Computer Technology is responsible for causing great leaps forward in communication technology. Computer Technology is responsible for causing great leaps forward in communication technology. Computers are all around us and come in sizes from a single chip to a whole room full of equipment. Computers are all around us and come in sizes from a single chip to a whole room full of equipment. Computer applications include online communication, word processing, desktop publishing and computer aided design. Computer applications include online communication, word processing, desktop publishing and computer aided design.

3. From Micros to Supercomputers Computers surround us even though we don’t always know that they are there. Computers surround us even though we don’t always know that they are there. To better understand the sizes and capabilities, computers are put into categories. To better understand the sizes and capabilities, computers are put into categories. These categories are microprocessors, microcomputers, minicomputers, mainframes and supercomputers. These categories are microprocessors, microcomputers, minicomputers, mainframes and supercomputers.

4. Microprocessors Integrated Circuits that perform and control arithmetic functions. Integrated Circuits that perform and control arithmetic functions. Embedded in appliances like ovens and washing machines. Embedded in appliances like ovens and washing machines. Used for single applications like controlling the time of an on-off cycle. Used for single applications like controlling the time of an on-off cycle.

5. Microcomputers Have microprocessor chips at their heart. Have microprocessor chips at their heart. Found in personal computers found in homes and offices. Found in personal computers found in homes and offices. Have a collection of integrated circuits with one microprocessor chip. Have a collection of integrated circuits with one microprocessor chip. Microcomputers memories can be very small or very large. Microcomputers memories can be very small or very large.

6. Mini Computers Relatively low cost and small Relatively low cost and small Were ‘mini’ back when computers were first coming out Were ‘mini’ back when computers were first coming out Term is rarely used Term is rarely used Usually are stand- alone computers Usually are stand- alone computers Has evolved into the ‘mid range server’ Has evolved into the ‘mid range server’

7. Mainframe Computers Large computers used by large companies, government agencies and universities for their administrative work. Large computers used by large companies, government agencies and universities for their administrative work. Could include making payroll cheques, records of employees, tracking orders, warehouse inventory etc. Could include making payroll cheques, records of employees, tracking orders, warehouse inventory etc. Mainframes can perform millions of instructions per second and often have billions of bytes of memory attached to them. Mainframes can perform millions of instructions per second and often have billions of bytes of memory attached to them.

8. Supercomputers Fastest and Largest Computers Fastest and Largest Computers Often used for research, analyzing satellite data or other very large problems. Often used for research, analyzing satellite data or other very large problems. Can perform several billions operations at one time. Can perform several billions operations at one time. Very expensive to purchase and operate. Very expensive to purchase and operate.

9. Information Exchange In order for the information that a computer produces to be useful, it has to be exchanged with people or other machines outside the computer. In order for the information that a computer produces to be useful, it has to be exchanged with people or other machines outside the computer. This exchange is called input/output. This exchange is called input/output.

10. Input Input is to provide information to a computer. Input is to provide information to a computer. The device you are most familiar with is the keyboard. The device you are most familiar with is the keyboard. People can issue instructions or provide raw data using the keyboard. People can issue instructions or provide raw data using the keyboard. Other forms of input include a mouse, floppy disk, CD-Rom, Scanners etc. Other forms of input include a mouse, floppy disk, CD-Rom, Scanners etc. Disks or CD’s can contain a program or data which the computer will load into its main memory. Disks or CD’s can contain a program or data which the computer will load into its main memory.

11. Computer Output Output can come in many forms Output can come in many forms Most common is the monitor or CRT screen (Cathode Ray Tube) which Converts electronic signals to visual images. Most common is the monitor or CRT screen (Cathode Ray Tube) which Converts electronic signals to visual images. Printers records the computers output on paper. Called a hard copy. Printers records the computers output on paper. Called a hard copy. Plotters use one or more pens whose position is controlled by a computer to create drawings on paper Plotters use one or more pens whose position is controlled by a computer to create drawings on paper

12. Data Communications Output of computers can be sent to other computers using a modem. Output of computers can be sent to other computers using a modem. This kind of information exchange is called data communications. This kind of information exchange is called data communications. Modems send computer data over standard telephone lines using sequences of tones to represent the bits of information to be sent. Modems send computer data over standard telephone lines using sequences of tones to represent the bits of information to be sent.

13. Online Communication You can have access to a lot of information by dialing a telephone number that connects your home computer to a mainframe computer. You can have access to a lot of information by dialing a telephone number that connects your home computer to a mainframe computer. This is referred to as being online, or surfing the net. This is referred to as being online, or surfing the net. The internet can provide news, weather, sports, banking, travel services and home shopping. The internet can provide news, weather, sports, banking, travel services and home shopping.

14. Electronic Mail Instead of sending letters through the mail, you can use a computer to send electronic messages. Instead of sending letters through the mail, you can use a computer to send electronic messages. In large companies, e-mail is a popular way to provide communication among their employees. In large companies, e-mail is a popular way to provide communication among their employees.

15. Word Processing Word processing software has made the job of typists easier. Word processing software has made the job of typists easier. Has features that “Typewriters” do not. Has features that “Typewriters” do not. Text can be checked for proper spelling, paragraphs can be moved from one place to another, columns and lines can be rearranged. Text can be checked for proper spelling, paragraphs can be moved from one place to another, columns and lines can be rearranged.

16. Computer-Aided Design Computers are changing the way people do technical drawing. Computers are changing the way people do technical drawing. With Computer-Aided design (CAD) systems, drafters can create, change and store more complex drawings than ever before. With Computer-Aided design (CAD) systems, drafters can create, change and store more complex drawings than ever before. Computer Aided Drafting has become one of the most important tools used by engineers, drafters and designers. Computer Aided Drafting has become one of the most important tools used by engineers, drafters and designers.

17. Desktop Publishing Computers are now able to produce whole pages with words, headlines and illustrations. Computers are now able to produce whole pages with words, headlines and illustrations. Using special software, desktop publishing lets you arrange copy and graphics on a computer screen just as you would like it to appear on paper. Using special software, desktop publishing lets you arrange copy and graphics on a computer screen just as you would like it to appear on paper.

18. All Purpose Tool Computer software provides the computer with specific instructions which direct it to do certain tasks. Computer software provides the computer with specific instructions which direct it to do certain tasks. Since computer programs can be changed to suit a particular application, a computer can be thought of a general purpose tool. Since computer programs can be changed to suit a particular application, a computer can be thought of a general purpose tool.