Transcript Computer Basics

Computer Basics
• A computer is one of the most brilliant inventions of
mankind and thanks to the computer we are able to
increase the amount of work we do each day, access vast
amounts of information, participate in our global
community, and stay instantly connected.
• Computers are machines that perform tasks or
calculations according to a set of instructions, they allow
us to efficiently store and process massive amounts of
data. The first fully electronic computers, introduced in
the 1940s, were huge machines that required teams of
people to operate. Compared to those early machines,
today's computers are amazing. Not only are they
thousands of times faster, they can fit on your desk, in
your lap, or even in your pocket.
Turning the Computer On
• When you turn on the power to a computer, the
first program that runs is usually a set of
instructions kept in the computer's read only
memory (ROM). This code examines the system
hardware to make sure everything is functioning
properly. When your computer is powered on it
runs a power-on self test (POST). The POST checks
the CPU, memory, and input/output systems for
errors. Once the POST has successfully completed,
the software loaded in read only memory (ROM),
will begin to access the computer's disk drives.
Turning the Computer On (cont.)
• In most computers, when the computer activates the
hard drive on startup, it finds the first piece of the
operating system (OS), called the bootstrap loader.
Did You Know: When you turn on a computer it is
commonly referred to as "booting up", this term is
short for bootstrap and used to describe the process
taken by the computer when it loads the OS and
prepares the system for use.
• After the operating system has loaded the user takes
back the control and the information processing cycle
begins.
OS & Software
• An operating system or OS, is a software program that
enables the computer hardware to communicate and
operate with the computer software. Without a
computer operating system, a computer would be
nothing more than a useless box of parts. As computers
have progressed so have the functionality of the
operating system.
• The first computers were all command driven, if a user
wanted to launch a program or print a document they
would have to know the correct command, nowadays
operating systems are driven by graphics. GUI - Short
for Graphical User Interface, a GUI Operating System
contains graphics and icons that a user can click to
perform a function or execute a program.
Types Operating Systems
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Windows 7 , 8 , and 10
Windows Vista
Windows XP
Mac OS
Mac OSX Panther
Unix
Linux
What is Software?
• Software is the term used for different types of
programs used on a computer. It is often divided into
application software (user driven) and system
software (which includes operating systems and any
program that supports application software).
• Software comes on CDs or DVDs. Today, much of the
software is downloaded over the Internet. Software
can be purchased or acquired as shareware (usually
intended for sale after a trial period), freeware (free
software but with copyright restrictions), and public
domain software (free with no restrictions).
What is Spyware?
• Spyware is a type of malicious software (malware) that is
installed on a computer and collects information about
users without their knowledge.
• Spyware programs can collect various types of personal
information including, Internet surfing habits and sites that
have been visited, it can also interfere with a users control of
the computer in other ways, such as installing additional
software and redirecting websites.
• Spyware is known to change computer settings, resulting in
slow connection speeds, different home pages, and/or loss
of Internet, or functionality of other programs. Although
programs exist to detect and rid computers of spyware they
are not always effective.
Information Processing Cycle
• What is the information processing cycle? The sequence of
events in processing information, which includes (1) input,
(2) processing, (3) storage and (4) output.
These processes work together and repeat over and over.
1)
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4)
Input—entering data into the computer.
Processing—performing operations on the data.
Storage—saving data, programs, or output for future use.
Output—presenting the results.
Input Devices
Input is the collection of raw data and putting it into an
information processing system or computer. Input devices can
be hardware devices, software, or user driven.
Examples of Hardware Input Devices:
• keyboard
• mouse
• scanner
• bar code reader
• joystick
• digital data tablet
• microphone
Input Devices (cont.)
Examples of Software or User Input:
• Programs are instructions that direct
the computer.
• Commands are key words that the user inputs to
perform a task. Examples include, choosing Open
on the File menu or using shortcut key, they may
also be chosen by clicking on a icon or button.
• User responded to the questions given by
computers, such as choosing OK, CANCEL, YES, or
NO or by typing in text, for example a file name.
Processing & Storage
Processing
• The system unit is the core of a computer system and the
main processing center. Usually it's a rectangular box that
holds many electronic components that process information.
The most important part of these components is the Central
Processing Unit (CPU) also called the processor. The CPU is
the brain of your computer it is the key component in
interpreting computer program instructions and processes
data. The next most critical element of a processing is RAM,
often referred to as "primary storage" or "main memory".
Random Access Memory (RAM) temporarily stores
information that the CPU uses while the computer is on and
is erased when the computer is turned off.
Processing & Storage(cont.)
Storage
• Computers usually have one or more disk drives,
commonly referred to as a hard drive—devices that
store information. The disk preserves the
information even when your computer is turned
off. All computers have a hard disk drive that can
hold massive amounts of information; they usually
serve as your computer's primary means of
storage, holding almost all of your programs and
files. The hard disk drive is normally located inside
the system unit.
Output Devices
• Output is the presentation of any data exiting
a computer system. Types of output include
visual, printed, or audio.
Types of output devices include:
• Monitor
• Printer
• Projector
• Speakers
Types of Computers
• Computers come in all sorts of shapes and sizes and
serve a variety of purposes. Not too many years
ago, computers were the size of a large room and
consumed huge amounts of power. However, with
the advances in technology, computers have shrunk
to the size of a watch. Depending on the processing
powers and sizes of computers, they have been
classified under various types.
Different types of Computers
Supercomputers: Highly calculation-intensive tasks
can be effectively performed by means of
supercomputers. Quantum physics, mechanics,
weather forecasting, molecular theory are best
studied by means of supercomputers.
Mainframe Computers: Large organizations use
mainframes for highly critical applications. Most of
the mainframe computers have the capacity to host
multiple operating systems and operate as a number
of virtual machines and can thus substitute for several
small servers.
Different types of Computers (cont.)
Microcomputers: A computer with a microprocessor
and its central processing unit is known as a
microcomputer. When supplemented with a
keyboard and a mouse, microcomputers can be called
as personal computers. A monitor, a keyboard and
other similar input output devices, computer
memory in the form of RAM and a power supply unit
come packaged in a microcomputer. These computers
can fit on desks or tables and serve as the best
choices for single-user tasks.
Personal Computers
Personal computers come in a variety of forms such as desktops,
laptops and personal digital assistants.
Desktops: A desktop is intended to be used in a single location and
are widely popular for daily use in workplace and home.
Laptops: Similar in operation to desktops, laptop computers are
miniaturized and optimized for mobile use. Laptops run on a single
battery or an external adapter that charges the computer batteries.
They are enabled with an inbuilt keyboard, touch pad acting as a
mouse and a liquid crystal display.
Personal Digital Assistants (PDAs): It is a handheld computer and
popularly known as a palmtop. It has a touch screen and a memory
card for storage of data. PDAs can also be effectively used as portable
audio players, web browsers and smart phones. Most of them can
access the Internet by means of Bluetooth or Wi-Fi communication.
Computer Speak
• Did you know that everything a computer does is
based on ones and zeroes? A computer represents
data using the binary system/binary code. Data can
be text, numbers, pictures, audio, and nearly any
other form of information that can be converted
into a string of bits, or binary digits, each of which
has a value of 1 or 0. The most common unit of
storage is the byte (8 bits.) A piece of information
can be handled by any computer whose storage
space (hard drive ) is large enough to
accommodate the binary representation of the
piece of information, or simply data.
Computer Speak (cont.)
Each 1 and each 0 is called a bit, each byte makes
up a letter or number and when added together
bytes the make up various units of measurements.
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8 bits make a byte
Kilobytes - 1,024 bytes
Megabyte - 1,048,576 bytes
Gigabytes - 1,024 megabytes
Terabytes - 1,024 gigabytes
Computer Speak (cont.)
Nowadays RAM, and storage capacity are all measured in
units and users are often confused. So what’s the
difference?
• RAM is the speed at which your computer runs, the
more gigs of RAM you have the faster your computer
will run.
• Hard drives, flash drives, and memory cards are all
examples of storage devices. Each of these devices
stores data and have various storage capacity. Your
computer hard drive might be 160 gig, where as the
memory card in your cell phone is 16 gig.