Study Guide

Types of ComputersTypes of computers include (but are not limited to)1.Personal computers

DesktopLaptop (notebooks)Tablet PC

2.Hand-heldPDA’s (personal digital assistants)MP3 playersCell phones

3.Mainframe computers- used by businesses and government to process large amounts of information

4.Supercomputers – largest, fastest and most powerful in existence

Computer System ComponentsComputer systems include hardware and software.Hardware refers to the physical components Software refers to the programs or list of instructions

that the computer needs to perform a specific task.System software is computer software designed to operate and

control the computer hardware and to provide a platform for running application software, such as the operating system

Application software is software you use to create documents, spreadsheets, presentations, etc.

The Operating System allocates system resources, manages storage space, maintains security, detects equipment failure, and controsl basic input and output.Data refers to information (words, numbers, graphics, etc.)Processing is modifying data

Computer Systems Components (continued)Motherboard is where processing tasks occur

Main electronic componentIs a circuit board

Microprocessor (CPU) Transistors and electronic circuits on

a silicon chipMounted on the motherboardResponsible for executing

instructions to process information

Computer System Components (continued)Cards are removable circuit boards to expand

the capabilities of the motherboardInput is the data or instructions you put into the

computer using keyboard, mouse, touchpad, scanner, camera, microphone

Output is the results of the computer processing. Devices used include printers, monitors, speakers.

Peripheral devices such as mouse, keyboards printers and storage devices accomplish input, output and storage functions

Commands are input instructions

Understanding MemoryTypes of memory include the following:1.Random access memory (RAM) –

temporarily holds programs and data while the computer is on and allows the computer to access that information randomly.

Consists of chips on cards that plug into the motherboard.

When the computer is off RAM is empty2.Cache memory (RAM cache or CPU cache)

–Special high speed memory chip on the

motherboard that stores frequently accessed and recently accessed data and commands

Understanding Memory3. Virtual memory – space on the computer’s

storage devices that simulate additional RAM. It is much slower than RAM4.Read only memory (ROM) – is a chip on the

motherboard that has been prerecorded with data that gives instructions (BIOS or basic input/output system) used to check the computer system’s components to make sure they are working and to activate the essential software that controls the processing function when the computer is turned on or booted up.

ROM never changes and it remains intact when the computer is turned off. It is called non-volatile or permanent memory

Understanding Storage MediaThe types of storage media are:1.Magnetic storage devices

Hard disk – magnetic oxide-covered metal platters sealed inside the computer

Tape – used to make back-up copies of data stored on hard drives

2.Optical storage devices – polycarbonate discs coated with a reflective metal on which data is recorded using laser technology

CD (Compact disc) – can store 700 MB of data DVD- can store between 4.7 and 15.9 GB of

data Blu-ray discs and HD-DVD – can store

between 15 and 50 GB of data

Understanding Storage Media3. Flash Memory

Flash memory cards – used in digital cameras, handheld computers and other devices

USB flash storage device – can store 32 MB – 16 GB of data. Popular for use as a secondary or backup storage device for date stored on a hard disk drive

Security ThreatsSecurity refers to the steps a computer owner takes

to prevent unauthorized use of or damage to the computer.

Malware is a broad term that describes any program that is intended to cause harm or convey information to others without the owner’s permission.

Virus is a program which instructs your computer to perform destructive activities.

Spyware tracks a computer user’s Internet usage and send this data back to the company or person that create it. It is contained in other software.

Security Threats (continued)Adware is software installed to generate

advertising revenue for the program's creatorSpoofed site - a website set up to look exactly

like another website to convince customers to enter personal information

Phishing - The practice of sending e-mails to customers or potential customers of a legitimate Web site asking them to click a link in the e-mail

Antivirus software protects against viruses, worms and Trojan horse types of malware