IT_Chapter_1B

Parts of the Computer System

• Computer systems have four parts

– Hardware

– Software

– Data

– User

• Hardware

– Mechanical devices in the computer

– Anything that can be touched

– Interconnected electronic devices used to control computer’s operation, i/p & o/p.

• Software

– Set of instructions (program)

– Tell the computer what to do

– Thousands of programs exist

• Data

– Pieces of information

– Computer organize and present data

• Users

– People operating the computer

– Most important part

– Tell the computer what to do

Information Processing Cycle

• Steps followed to process data

• Input

• Processing

• Output

• Storage

Essential Computer Hardware

• Computers use the same basic hardware

• Hardware categorized into four types

Processing

• Procedure that transforms raw data into useful information

• Computer uses two components

– Processor

– Memory

• Processing devices (Processor)

– Brains of the computer

– Carries out instructions from the program

– Manipulate the data

– Most computers have several processors

– Central Processing Unit (CPU)

• Memory devices

– Stores data or programs (set of chips)

– Random Access Memory (RAM)

• Volatile

• Stores current data and programs

• More RAM results in a faster system

– Read Only Memory (ROM)

• Permanent storage of programs

• Holds the computer boot directions

• Input and output devices

– Allows the user to interact

– Input devices accept data

• Keyboard, mouse

– Output devices deliver data

• Monitor, printer, speaker

– Some devices are input and output

• Touch screens

• Communication devices

• Storage devices

– Hold data and programs permanently

– Different from RAM

– Magnetic storage

• Floppy and hard drive

• Uses a magnet to access data

– Optical storage

• CD and DVD drives

• Uses a laser to access data

Software Runs The Machine

• Tells the computer what to do

• Reason people purchase computers

• Two types

– System software

– Application software

• System software

– Most important software

– Controls computers h/w

– Operating system

• Windows XP

– Network operating system (OS)

• Windows Server 2003

– Utility

• Symantec AntiVirus

• Application software

– Accomplishes a specific task

– Most common type of software

• MS Word

– Covers most common uses of computers

Computer data

• Fact with no meaning on its own

• Stored using the binary number system

• Data can be organized into files

Computer users

• Role depends on ability

– Setup the system

– Install software

– Mange files

– Maintain the system

• “Userless” computers

– Run with no user input

– Automated systems