Transcript Computer Components

Study Guide
Types of Computers
Types of computers include (but are not limited to)
1. Personal computers
Desktop
Laptop (notebooks)
Tablet PC
2.
Hand-held
PDA’s (personal digital assistants)
MP3 players
Cell phones
Mainframe computers- used by businesses and
government to process large amounts of information
4. Supercomputers – largest, fastest and most powerful in
existence
3.
Computer System Components
Computer 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 component
 Is a circuit board
 Microprocessor (CPU)
 Transistors and electronic circuits on a
silicon chip
 Mounted on the motherboard
 Responsible for executing instructions to
process information
Computer System Components
(continued)
 Cards are removable circuit boards to expand the
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capabilities of the motherboard
Input 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 Memory
Types 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 empty
2. 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 Memory
3. Virtual memory – space on the computer’s storage
devices that simulate additional RAM.
 It is much slower than RAM
4.
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.
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ROM never changes and it remains intact when the
computer is turned off. It is called non-volatile or
permanent memory
Understanding Storage Media
The 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
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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 Media
3. 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 Threats
Security 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 creator
 Spoofed 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