Information Technology BTA3O - Unit 1

Computer Hardware Functions Input Devices Memory RAM ROM Central Processing Unit Secondary Storage Devices Output Devices

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 256 MB – 16 GB Hard disk: 50 GB – 2 TB CD: 700 - 800 MB DVD: 4.7 GB - 17 GB 1 BYTE = 1 CHARACTER 1 KILOBYTE = 1000 BYTES 1 MEGABYTE = 1000 KB or 1,000,000 KILOBYTES 1 GIGABYTE = 1000 MB or 1,000,000,000 KILOBYTES 1 TERABYTE = 1000 GB or 1,000,000,000,000 KB

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 ROM = Read Only 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 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 Ring Network Bus 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 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.

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