This applet was design to help you read the value. I am sorry that you did not understand it.

Use the following snap shot image of the applet as an example.

1. You will find 0. pass the 9.0 mm line so the distance is more than 9.0 mm

2. Find the line which is aligned for both rulers. Read the number from the moving ruler, which correspond to .7 mm

3. Add those two together, so you have 9.7 mm.

Is it simple enough. It is similar for the micro-meter. Use the above image as an example:

You will find the distance is more than 5.5 mm and you will find .28mm from the rotating part.

So the final result is 5.5mm+0.28mm=5.78mm