Information Technology

BTA3O - Unit 1

CentralProcessing

Unit

Memory

RAMROM

Input Devices

Output Devices

Secondary StorageDevices

Computer Hardware Functions

Input Devices

Keyboard Mouse Graphic Tablets Ports (USB, Serial, etc.) Modems Scanners Digital Cameras

Output Devices

Monitors Ports Modems Printers Plotters Disk Drives Machine Interfaces

Ports and Connectors

Ports are categorized by their mode of transmission:– Parallel port

Standard parallel port (printers) Small Computer System Interface (SCSI)

– Serial port Standard serial port (modem, mouse) Musical instrument digital interface (MIDI) Universal Serial Bus (USB)

Connectors– Male have one or more pins– Female have locators that match the pins on the male

Storage

Hard Drive Floppy Drives CD-ROM RW-CD-ROM DVD RW-DVD Flash Memory

Disk Capacities

Floppy: 1.4 MB Flash Memory 32 MB – 2 GB Hard disk: 20 GB – 1000 GB CD: 700 - 800 MB DVD: 4.7 GB - 17 GB

1 BYTE = 1 CHARACTER1 KILOBYTE = 1000 BYTES1 MEGABYTE = 1000 KB or 1,000,000 KILOBYTES1 GIGABYTE = 1000 MB or 1,000,000,000 KILOBYTES

Magnetic Disk Storage

Disk Fragmentation

Fragmented disk shows spaces where data has been removed

Defragmenting has placed all files in contiguous spaces

Defragmenting a drive will increase efficiency for file retrieval

CD-ROM and Optical Disks

CD-ROM (compact disk ROM)– 650 MB of information

CD-R (compact disk-recordable) DVD-ROM (digital versatile disk)

– 4.7 gigabytes

DVD-ROM Dual Layer– 9.4 gigabytes (movies)

Magneto-optical (MO)– 230 MB, 650 MB, 1.3 GB– supports read and write operation

Bays

Areas inside the computer base, specifically designed to facilitate the installation of additional equipment

External Bays– one open end for loading and unloading storage media such as diskettes, tapes

and CD-ROMS Internal Bays

– completely enclosed - inside the case– for hard disk drives

Memory

RAM = Random Access Memory– The space available to a computer to use while

performing operations. The space is emptied out when the computer is turned off.

ROM = Read Only Memory– The memory programmed by the manufacturer

containing system information.– Cannot be overwritten without special software.

Power Supply

The purpose of the power supply is to convert the AC power to a more useable form for the computer.

Newer machines use less power allowing CPUs to run faster without overheating.

Operating Systems

The operating system acts as the interface between the application and the computer system.

The following are examples of operating systems– Microsoft Windows, Unix, Linux, and Macintosh

Operating System SoftwareOperating System Software

Role of Operating System Software is to:– perform common computer hardware functions– provide a user interface– manage system memory– manage processing tasks– provide networking capability– control access to system resources– manage files

Networking

A network is defined as two or more computers connected together

– Peer-to-peer when a server is not involved– Client-server when a server is involved

Uses and Benefits of a LAN– Security through id and password– Shared peripherals– Shared storage– Shared Applications– Reliability and Resilience– centralized backup systems for data recovery– centralized virus protection

Types of Networks

Star Network– Centralized hub (typical systems)– Each machine runs independently from

the other, but hubs connect Ring Network

– All machines arranged in a ring– Built in redundancy with dual-ring– Fibre optics and token ring

Bus Network– All machines on the same line– Difficult to repair but inexpensive to

construct

Adapting to ChangeAdapting to Change

Adapting to an ever changing environment is a challenge all businesses must face.– Business end-users must define business needs,

evaluate options, and select the hardware and software that provide a cost-effective solution to those needs.

– The information system industry continues to undergo constant change; users need to be aware of recent trends to remain current.

ConclusionConclusion

Hardware devices work together to perform input, processing, data storage, and output.

Networks allow computers to share information and resources.

There are two main categories of software: systems softwaresystems software and application softwareapplication software

An operating system (OS) is a set of computer programs that control the computer hardware to support users’ computing needs.