Intro to Computers Computer Applications. What is a Computer? Initially the term computer referred to an individual whose job it was to perform mathematical.

Intro to Computers

Computer Applications

What is a Computer?

• Initially the term computer referred to an individual whose job it was to perform mathematical computations.

• Today, it refers to an electronic device that accepts data (input), then processes that data producing information (output).

What is a Computer

• A computer is just a machine. It does not think thus has no intelligence. It only knows what we tell it. It follows our instructions precisely.

Information Processing Cycle

• We use computers as a tool to assist users in converting data into information.

• User: Anyone who communicates with a computer or uses its information

• Data: Raw facts, figures, numbers, words, images

• Information: data that has been processed into a form that is more meaningful & useful

Information Processing Cycle

Information Processing Cycle

• The computer’s hardware operates under detailed sets of instructions, software, that control every aspect of its operation.

• Hardware: a computer’s electronic and mechanical equipment

• Software: instructions that tell the hardware how to perform

Information Processing Cycle

• Software controls:

– How the screen appears– How to accept the user’s commands– How commands are interpreted & executed

– How the output is to be presented

Information Systems

• The computer’s hardware and software work together to form an information system.

Information Systems

• Primary components1. People2. Input Devices 3. System Unit4. Output Devices5. Communication Devices6. Storage Units7. Software

• People input data into the computer and receive the processed information.

Input Devices

• These are devices that allow users to enter data and instructions.

• Primary input devices include:– Keyboard– Mouse– Microphone– Scanners– Digital cameras

Output Devices

• Output Devices convey information to the user.

• Primary output devices include:– Monitors– Printers– Speakers

System Unit

• The case containing the internal components.

• The System Unit is composed of two primary parts: 1. The Central Processing Unit (CPU)

2. Main Memory or RAM

Central Processing Unit

• The CPU contains the circuitry that interprets and carries out the basic instructions that operate the computer.– It is known as the “brain” of the computer.

• The CPU is designed into a chip, often referred to as the microprocessor.

Central Processing Unit

• The CPU is comprised of two parts:

– The control unit• Controls the signal between the ALU, Main Memory, & the input/output devices

– The arithmetic logic unit (ALU)• Performs all arithmetic & logical operations

Main Memory

• Main Memory or Random Access Memory (RAM)

• RAM is a buffer where all data must be temporarily stored before processing.

• Main Memory is measured in megabytes.

Main Memory• Together, the CPU and the RAM make up the computer’s system unit and help dictate a computer’s capacity.

• The more instructions the CPU processes per second, the faster information can be processed.

• The more memory a computer contains, the more information can be stored and the faster information can be processed.

Which would be faster

Computer 1512MB RAM

Computer 21000MB RAM

Hard Drive

• “Long-term Memory”

• A hard drive stores a computer’s written data and information.

Storage Units

• Storage Units provide permanent storage for both software and data.

• Primary storage devices include:– Floppy Disks– Zip Disks– CD-Roms– Hard Disks– USB Flash Drives

Software

• Software provides the instruction sets needed by a computer.

• Computers use two types of software:1. Application Software

2. System Software

Software

• Application Software– Software designed to perform specific tasks.

Software

• System Software– Controls the operation of the computer and

its devices.

– It is the interface between the user, applications and hardware.

– There are two types of system software:

1. Operating System (Windows)

2. Utility Programs (Virus Scan, Volume Control)