Touch Pad Is a small,Flat surface over which the user moves his finger.
The movement of finger controls the cursor on the monitor screen.It is also
known as Track pad.
A Touch pad also contains one or more buttons near it.These buttons
work like mouse buttons.Touch pads are commonly used in notebook
computers or laptop computers.
The disadvantage of Touch pad is that it is very sensitive and require
very much care while using it.
A Track ball can be used as An alternative to a mouse.This device has
buttons similar to those on mouse.It has large rotating ball on its top.
The body of track ball is not moved. The ball is rolled with finger.
The position of the cursor on the screen is controlled by rotating the ball.
An advantage of track ball is that it takes less space to move than mouse.
Track ball is often included in Laptop computers.It can be used as separate