Computers & Computer Systems Lesson 1

Computing Fundamentals

A World of Computers

• Computer Literacy - Knowledge and understanding of computers and their uses

Defining Computers • Computer – an electronic device that:

• Receives data (input)

• Processes data

• Stores data &

• Produces a result (output)

• Information Processing Cycle – the action of these four basic operations

Components of a Computer

• Input Devices

• System Unit (Processor and Memory)

• Output Devices

• Storage Devices

Input Devices

• Input Device – any hardware component that allows you to enter data and instructions into a computer

• Examples:

• Keyboard

• Mouse

• Audio Input

• Web Cam

• Scanner

• Camera

System Unit

• System Unit – A case that contains electronic components of the computer used to process data

Processor

• Processor – Interprets and carries out the basic instructions that operate a computer; Central Processing Unit (CPU) or the brains of the computer

• Control Unit – directs and coordinates most of the operations in the computer; the boss

• Arithmetic/Logic Unit (ALU) – performs arithmetic, comparison, and other operations

Units of Speed

Unit Characters

Hertz Approx. 1 character

Kilohertz Approx. 1,000 characters

Megahertz Approx. 1,000,000 characters

Gigahertz Approx. 1,000,000,000 characters

Terahertz Approx. 1,000,000,000,000 characters

Memory

• Memory – consists of electronic components that store instructions waiting to be executed and data needed by those instructions

• RAM – Random Access Memory or main memory

• Keeps data and instructions temporarily or will erased when the computer is shut off (Measured in bytes)

• ROM – Read Only Memory

• Can be read but not modified (system files)

Units of Memory

Unit Character

Byte Approx. 1 character

Kilobyte Approx. 1,000 characters

Megabyte Approx. 1,000,000 characters

Gigabyte Approx. 1,000,000,000 characters

Terabyte Approx. 1,000,000,000,000 characters

Output Devices

• Output Devices – Hardware components that convey info to one or more people

• Examples:

• Monitors

• CRT

• LCD panel

• Gas plasma display

• Printers (dpi/ppm)

• Laser

• Inkjet

• Speakers

Connecting Input & Output Devices to the Computer • Port – an interface to which

a peripheral device attaches to or communicates with the system unit

• Universal Serial Bus (USB) – the most common used port for devices

• FireWire – used for high speed digital and audio devices

Identifying Types of Storage Devices

Storage Device Description Examples

Magnetic Discs Use magnetic particles to store items on a disk’s surface

Hard disks, magnetic tape, 3½ inch & ZIP disks

Optical Storage Devices

Use laser technology to read and write data on silver platters

CDs and DVDs

Solid-State Storage Media

Removable medium that uses integrated circuits to process

Miniature mobile storage media, USB flash drive

Network Drives Drive located on a computer other than the user’s local system

Components of a Computer

Classifying Computers

Types Definition Examples

Desktop Computers

Designed so that all components fit on or under a desk

PC (Windows based) or Apple Macintosh

Notebook (Laptop) Computer

Small, portable, personal computers that contain the monitor with a built-in keyboard

Server Used by small to medium-size companies and can support a few users or hundreds of users

File server, database server, or web server

Classifying Computers

Types Definition Examples

Mobile Devices

Generally fit in the palm of your hand

Calculators, smart phones, cell phones, handheld games, electronic organizers, & PDAs

Classifying Computers

Types Definition Examples

Tablet PC A personal computer similar in size and thickness to a notepad

Tablet Devices

Use an embedded operating system, but do not support full feature operating systems like Tablet PCs

Classifying Computers

Types Definition Examples

Mainframe computer

Large expensive computer, capable of supporting up to thousands of users

Super-computer

Fastest type of computer, used for specialized applications to process enormous amounts of data

Classifying Computers

Types Definition Examples

Embedded Computers

Found in devices to perform specific tasks

Digital watch, MP3 player, appliances, etc.

Portable music/ media players

Store and play back music and videos

MP3 players and portable DVD players

Classifying Computers

Types Definition Examples

Computer game systems

Specialized computers used to play games

Electronic book readers

Displays an electronic version of a traditional print book

Computer Performance Factors

• Microprocessor – the faster the processor, the more instructions it can process

• RAM – larger memory allows the processor to move faster

• Hard disk – the bigger and faster the hard drive, the faster the data is processed

• Video – having adequate video memory allows the processor to perform to its full potential