Transcript Computer Basics - Gustavo Alatta

Computer Basics
- Introduction to Computer.
- Computer Types.
- Operating Systems.
By Gustavo Alatta
Introduction to Computers
We are living in an information age dependent upon digital
information. Digital information is electronic information, the
result of computer processing. Every type of job relies upon
getting information, using it, managing it, and relaying
information to others. Computers enable the efficient processing
and storage of information.
Do not think of a computer merely as the machine with the
keyboard and the mouse, although that might be true for some
types of computers. Embedded computers may be inside your
household appliances, the VCR, the automobile, planes, trains,
powerplants, water purification plants, calculators, and even
inside a few toys. These embedded computers are very small.
They affect our lives each day. Why, even modern traffic lights
operate with computers. They are all around us. Think of
additional ways in which computers affect our lives each day.
Computer Types
Computers are showing up everywhere
you look, and even in places you can't
see. Computers check out your
groceries, pump your gas, dispense
money at the ATM, turn the heat on and
off, control the way your car runs.
They're everywhere! They're
everywhere!
What is a Computer
A computer is an electronic device that
executes the instructions in a program. A
computer has four functions:
Input
a. accepts data
Processing
b. processes data
Output
c. produces output
Storage
d. stores results
In the lessons that follow we will study the parts of
the computer and each of the four parts of the
Information Processing Cycle.
Some Beginning Terms
Hardware : The physical parts of the computer.
Software
: The programs (instructions) that tell
the computer what to do
Data
: individual facts like first name, price,
quantity ordered
Information : data which has been massaged into a
useful form, like a complete mailing address
Default
: The original settings; what will happen
if you don't change anything.
What makes a computer
powerful?
Speed A computer can do billions of
actions per second.
Reliability Failures are usually due to
human error, one way or another.
(Blush for us all!)
Storage A computer can keep huge
amounts of data.
Computer Types
Personal or Microcomputers
Computers for personal use come in all shapes and sizes, from tiny
PDAs (personal digital assistant) to hefty PC (personal computer)
towers. More specialized models are announced each week - trip
planners, expense account pads, language translators...
Tablet
PC
Hand-held
(HPC)
PDA
Laptop/Notebook
Desktop
Tower
Workstation
Computer Types (cont…)
Personal or Microcomputers
When talking about PC computers, most people probably think
of the desktop type, which are designed to sit on your desk.
(Bet you figured that one out!) The tower and the smaller minitower style cases have become popular as people started needing
more room for extra drives inside. Repairmen certainly
appreciate the roominess inside for all the cables and circuit
boards ... and their knuckles.
A workstation is part of a computer network and generally
would be expected to have more than a regular desktop PC of
most everything, like memory, storage space, and speed.
Computer Types (cont…)
Personal or Microcomputers
The market for the smallest PCs is expanding rapidly. Software
is becoming available for the small types of PC like the palmtop
(PPC) and handheld (HPC). This new software is based on
new operating systems like Windows CE (for Consumer
Electronics). You may find simplified versions of the major
applications you use. One big advantage for the newer programs
is the ability to link the small computers to your home or work
computer and coordinate the data. So you can carry a tiny
computer like a PalmPilot around to enter new phone numbers
and appointments and those great ideas you just had. Then later
you can move this information to your main computer.
With a Tablet PC you use an electronic stylus to write on the
screen, just like with a pen and paper, only your words are in
digital ink. The Tablet PC saves your work just like you wrote it
(as a picture), or you can let the Hand Recognition (HR)
software turn your chicken-scratches into regular text.
Computer Types (cont…)
Main frame
The main frame is the workhorse of the business world. A
main frame is the heart of a network of computers or
terminals which allows hundreds of people to work at the
same time on the same data. It requires a special
environment - cold and dry
Computer Types (cont…)
Supercomputers
The supercomputer is the top of the heap in power and
expense. These are used for jobs that take massive
amounts of calculating, like weather forecasting,
engineering design and testing, serious decryption,
economic forecasting, etc.
The first Cray supercomputer was introduced in 1976
Computer Types (cont…)
Distributed or Grid Computing
The power needed for some calculations is more than even a single
supercomputer can manage. In distributed computing using a PC grid
many computers of all sizes can work on parts of the problem and their results
are pooled. A number of current projects rely on volunteers with computers
connected to the Internet. The computers do the work when they are not busy
otherwise.
The projects that need distributed computing are highly technical. For
example, the SETI@Home project looks for signs of intelligent communication
in radio signals coming from space. (SETI stands for Search for ExtraTerrestrial Intelligence.)
If you volunteer your computer for this project, you might be asked to load a
small screen-saver program onto your own computer. When the computer is not
busy, the screen saver comes on. The program downloads some signal data,
starts to analyze it, and later reports the results back to SETI@Home. Once the
program is installed, you do not have to do anything else but watch the progress
in the screen saver.
Another method does not use a screen saver, but uses any idle time on your
computer to work on the project. Results are sent to the project's home over the
Internet.
Other Important Terms
Server
The term server actually refers to a computer's function rather than to
a specific kind of computer. A server runs a network of computers. It
handles the sharing of equipment like printers and the communication
between computers on the network. For such tasks a computer would
need to be somewhat more capable than a desktop computer. It would
need:




more power
larger memory
larger storage capacity
high speed communications
Other Important Terms
Minicomputer
The minicomputer has become less important since the PC has
gotten so powerful on its own. In fact, the ordinary new PC is much
more powerful than minicomputers used to be. Originally this size was
developed to handle specific tasks, like engineering and CAD
calculations, that tended to tie up the main frame.
Other Important Terms
Microcontrollers or Embedded Computers
- The smallest class of computers.
- Are the type of computer processors found in small
machines and appliances, such as microwave ovens.
Operating Systems
A computer operating system acts like a manager or supervisor
of a PC. The operating system, or OS for short, manages your
computer’s resources such as your PC’s memory.
Computer operating systems are generally classified as being
either a GUI, i.e. graphical user interface, type or a command
driven type.
Popular operating systems which are GUI types include:
Windows  2000 Me, Windows  NT and OS / 2. Popular
operating systems, which are command driven types include:
DOS, which stands for Disk Operating System, and UNIX.
The GUI operating systems work using a “ point and click ”
environment since users are able to use pointing devices such
as a mouse to select icons which are used to open programs or
files.
Operating Systems
The command driven operating systems work using commands,
which the user must be familiar with, in order to run some
program or perform some other task. For example, passwd is a
common UNIX command, which allows the user to change a
login password.
Operating systems software should be distinguished from
applications software. Applications software cannot run without
operating system software.
Applications software includes word processors, spreadsheets,
Web browsers, encyclopedia software, almanacs, entertainment
software and others.
Operating Systems
Popular Computer Operating Systems
Windows Server 2003 Me
Windows XP
Windows 2000
Windows 98
Windows NT
OS / 2
MAC OS
DOS
UNIX
LINUX
NetWare