Caliper: A precision tool used to measure the internal and external dimensions of an object. It can measure thickness, diameter, or depth with high accuracy.
Micrometer: Used for measuring the thickness or diameter of small objects with high precision.
Ruler/Tape Measure: Used for general length measurements.
Vernier Scale: A tool used to measure small dimensions with more precision than a standard ruler.
A Caliper is used to measure the outside, inside, and depth dimensions of objects. It is particularly useful in mechanical and automotive work, where precision is essential.