How to read a vernier caliper

How you take measures with a Vernier calipers.
A Vernier Caliper is a handy device in a tool room. This is a simple versatile device, can measure the length, diameter of the shafts and other external dimensions. This can also be used for measuring inside dimensions (though limited) like inside diameter. So here we have a general procedure to take reading of that measuring device:

1. Before measuring, do make sure the caliper reads 0 when fully closed. If the reading is not 0, adjust the caliper’s jaws until you get a 0 reading. That is the zero’s on both main and vernier scale coincides.
2. Close the jaws lightly on the item which you want to measure. If you are measuring something round, be sure the axis of the part is perpendicular to the caliper. Namely, make sure you are measuring the full diameter. An ordinary caliper has jaws you can place around an object, and on the other side jaws made to fit inside an object. These secondary jaws are for measuring the inside diameter of an object. Also, a stiff bar extends from the caliper as you open it that can be used to measure depth.
3. How to read the measured value:
1 Read the main scale reading to the left of the 0-mark on the vernier scale.
2). Look along the ten marks on the vernier scale and the marks on the adjacent main scale, until you find the two that most nearly line up.
4). To get the correct reading, ad the reading on the main scale and reading on the vernier scale multiplied by least count.

One important thing to note in above example, is the least count of Venier caliper is 0.02 mm. Least count is the minimum measurement it can take. And to find the least count, we use:
Least count of vernier callipers = Value of 1 main scale div / total vernier scale div