Computer: It is an electronic device which takes data inputted by user, process it and gives us an output.
User: A person who operates/use computer is a user.
What is Data?
Any types of information saved in the computer is called Data. Example; audio files, video, image, documents, softwares etc.
Data Units: Computer memory, disk space & file size measure in one standard unit is called bits & bytes. Where
0 or 1 binary digit = 1 bit
4 bits = 1 nibble
8 Bits = 1 byte (1 character)
1024 bytes =1 Kilo byte
1024 KB = 1 Mega byte.
1024 MB = 1 Giga byte
1024 GB = 1 Tera byte
1024 TB = 1 Peta byte
1024 PB = 1 Exa byte
Speed is measured in herz. Same as above.
Types of Computer
(On the basis of size and computation power, it is categorized into)
1. Super computers (Fastest –used in research, huge numerical calculation etc)
2. Main frame computers (Have many terminals- used in big business organizations)
3. Mini computers (Smaller than main frames but bigger than personal computers)
4. Microcomputers (known as pc-personal computer)
Monitor: The monitors are the most common output devices. It displays characters and graphics. CRT and LCD are two commonly used types of monitors.
1. CRT Monitors (Cathode Ray Tube)
CRT Monitor is named because it uses large vacuum tubes called a Cathode Ray Tube (CRT). It looks like a common television screen. The CRT monitors are relatively bigger in size than other monitors but it is cheaper.
2. LCD Monitors (Liquid Crystal Display)
LCD Monitors are flat-panel monitor. It uses a special kind of liquid crystal for display. LCD monitors are comparatively light in weight and portable monitors but they are expensive.
Printer
The printer is one of the most common output devices. It provides data program and other results in a permanent readable form. That is in a sheet of paper. The output produced from printer is known as Hard Copy.
Basically, printers are categorized into two types: Impact and Non-Impact.
Impact Printer
An impact printer is similar to a typewriter in which characters are printed by physical striking of type device over an inked ribbon. It is a noisy printer.
1. Dot-matrix printers,
2. Daisy wheel printers,
3. Drum printers etc. fall under the category of impact printer.
Non-Impact Printer
A non-impact printer is a quiet printer because it doesn't strike on the paper to characters. Rather, characters are formed by using heat (in thermal printers), light (in laser printers) and ink-spray (in ink jet printers). These printers are faster more reliable than impact printer but they are expensive.
1. Ink Jet Printers
These are non-impact printers. They print Characters by spraying small drops of ink into paper. Ink jet printers produce high quality output because the characters are formed by dozens of tiny ink dots. They provide the resolution of at least 360 dots per inch (dpi).
2. Laser Printer
A laser printer can produce higher quality output of text or graphics. It looks like a, photocopier. The laser printer uses a laser beam to create images. Speed and quality are distinguishing features of laser printers. The common laser printers provide resolutions of 300 or 600 dpi. And, they can print several pages per minute. But, laser printers are more expensive compared to other types of printers.
3. Potter
The plotter is an output device that ' can create drawings, charts and graphics. Some printers can also produce such graphics but plotters are used when we require a high quality drawing and graphics.
Some common types of plotters are - Drum plotter, Flat bed Plotters, Electro static plotters etc
User: A person who operates/use computer is a user.
What is Data?
Any types of information saved in the computer is called Data. Example; audio files, video, image, documents, softwares etc.
Data Units: Computer memory, disk space & file size measure in one standard unit is called bits & bytes. Where
0 or 1 binary digit = 1 bit
4 bits = 1 nibble
8 Bits = 1 byte (1 character)
1024 bytes =1 Kilo byte
1024 KB = 1 Mega byte.
1024 MB = 1 Giga byte
1024 GB = 1 Tera byte
1024 TB = 1 Peta byte
1024 PB = 1 Exa byte
Speed is measured in herz. Same as above.
Types of Computer
(On the basis of size and computation power, it is categorized into)
1. Super computers (Fastest –used in research, huge numerical calculation etc)
2. Main frame computers (Have many terminals- used in big business organizations)
3. Mini computers (Smaller than main frames but bigger than personal computers)
4. Microcomputers (known as pc-personal computer)
Monitor: The monitors are the most common output devices. It displays characters and graphics. CRT and LCD are two commonly used types of monitors.
1. CRT Monitors (Cathode Ray Tube)
CRT Monitor is named because it uses large vacuum tubes called a Cathode Ray Tube (CRT). It looks like a common television screen. The CRT monitors are relatively bigger in size than other monitors but it is cheaper.
2. LCD Monitors (Liquid Crystal Display)
LCD Monitors are flat-panel monitor. It uses a special kind of liquid crystal for display. LCD monitors are comparatively light in weight and portable monitors but they are expensive.
Printer
The printer is one of the most common output devices. It provides data program and other results in a permanent readable form. That is in a sheet of paper. The output produced from printer is known as Hard Copy.
Basically, printers are categorized into two types: Impact and Non-Impact.
Impact Printer
An impact printer is similar to a typewriter in which characters are printed by physical striking of type device over an inked ribbon. It is a noisy printer.
1. Dot-matrix printers,
2. Daisy wheel printers,
3. Drum printers etc. fall under the category of impact printer.
Non-Impact Printer
A non-impact printer is a quiet printer because it doesn't strike on the paper to characters. Rather, characters are formed by using heat (in thermal printers), light (in laser printers) and ink-spray (in ink jet printers). These printers are faster more reliable than impact printer but they are expensive.
1. Ink Jet Printers
These are non-impact printers. They print Characters by spraying small drops of ink into paper. Ink jet printers produce high quality output because the characters are formed by dozens of tiny ink dots. They provide the resolution of at least 360 dots per inch (dpi).
2. Laser Printer
A laser printer can produce higher quality output of text or graphics. It looks like a, photocopier. The laser printer uses a laser beam to create images. Speed and quality are distinguishing features of laser printers. The common laser printers provide resolutions of 300 or 600 dpi. And, they can print several pages per minute. But, laser printers are more expensive compared to other types of printers.
3. Potter
The plotter is an output device that ' can create drawings, charts and graphics. Some printers can also produce such graphics but plotters are used when we require a high quality drawing and graphics.
Some common types of plotters are - Drum plotter, Flat bed Plotters, Electro static plotters etc
