Computer , Parts of computer ,Functions of Computer , Basic of IT

1. InteractingWithYour
Computer

2.  THE KEYBOARD:
ITSAN INPUT DEVICE
FOR
ENTERING
NUMBERS &
TEXTS.
 THE MOUSE:
ITSAN INPUT DEVICE
THATYOU CAN MOVE AROUND
AND CONTROLS
POINTER.

3.  ITS AN INPUT DEVICE FOR ENTERINGTEXT AND
NUMBERS.
 KEYBOARD HAS ABOUT 100 KEYS.

4.  The alphanumeric keys _ the area of keyboard that
looks like a typewriter’s keys.
 This arrangement is called the QWERTY because the first
SIX keys on top of the row of letters are Q,W,E,R,T,Y.

5. MODIFIERKEYS
SHIFT
ALT
CTRL
The SHIFT,ALT and CTRL keys are called
MODIFIER KEYS because they modify
the input of other keys.

6.  The numeric keypad
looks like a calculator’s keypad, with its 10 digits and
mathematical operators
(+, - , *, /).
 Numeric keys also features NUM LOCK key.

7.  The function keys, which are labeled F1,F2 and so on
are usually arranged in row along the top of the
keyboard.

8.  Most standard keyboards also include a set of cursor-
movement keys , which let you move around the screen
without using a mouse.

9.  IBM-compatible keyboard features six special-
purpose keys, each of which performs a unique
function.

10. KEYBOARD
CONTROLLER
1. A key is pressed on the keyboard
KEYBOARD
BUFFER
SYSTEM
SOFTWARE
4.The system software respond to
the interrupt by reading the scan
code from the keyboard buffer
2.The keyboard controller sends
the scan code for the key to the
keyboard buffer.
3.The keyboard controller
sends an interrupt request
to the system software
5.The system
software passes
the scan code
to the CPU.

11.  A mouse is an input device that you can move around on flat
surface(usually on a desk or keyboard tray) and controls
the pointer.
PRIMARY
BUTTON:
1.Click
2.Double-Clicking
3.Selection
4.Dragging
SECONDARY
BUTTON:
1.To bring menus

12.  The primary goal of “mouse variants” are to provide ease of
use while taking up less space than a mouse.
Following are some variants of mouse explained in this chapter :
TRACKBALL TRACKPAD TRACKPOINT

13.  Trackball is a pointing device that works like an upside-down mouse you
rest your index finger or thumb on an exposed ball, then place your other
fingers.
 You do not have to move the whole device , a trackball requires less
space.
BALL:
Move the ball to
move the pointer
on the screen

14.  The movement of a finger across a small touch-sensitive surface is
translated into pointer movement on computer screen.
 Touch sensitive screen maybe only 1.5 or 2 inches, so finger never has to
move far.

15.  Many portable computers now feature a small joystick positioned near
the middle of the keyboard , typically between the G and H keys .The
joystick is controlled with either forefinger, and it controls movement of
pointer on screen.

16.  The term ergonomically correct means that a tool or workplace is
designed to work properly with the human body , and thus reduces the
risk of strain and injuries.
REPETITIVE STRESS INJURIES
This ailment is called repetitive stress injuries (RSIs) or
repetitive strain injuries and result from continuously using
the body in a way it was not designed to work.
CARPALTUNNEL SYNDROME:
A wrist or hand injury caused by using a keyboard for long period of time.

17.  If you use computer frequently, you can avoid RSIs by adopting a few
good work habits, and by making sure that your hardware and
workspace are set up in an ergonomically friendly way.
 Following are some ways to avoid serious keyboard related injuries:
CHAIR:
1. Make it first priority to use comfortable chair.
USE ERGONOMIC KEYBOARD:
2. An ergonomic keyboard allows you to hold your hands in more normal
position while typing.

18. USE A PADDEDWRIST SUPPORT:
If you type a lot , a wrist support can be helpful by allowing you to rest
your hands comfortably when you are not actually typing.
KEEPYOURWRIST STRAIGHT:
While typing your hands should be in a straight line with your
forearms.
SIT UP STRAIGHT:
Sit up straight and avoid crossing your legs in front of you or under your
chair for long period.
TAKE FREQUENT BREAKS:
Get up and move around for a few minutes each hour, and stretch occasionally
throughout the day.