Types of measurement Direct measurement It is a simple method. The quantity to be measured directly without any calculations. Measuring length, time are some direct measurements. Some of direct measurement instruments are, Scale, Vernier caliper, Stop watch etc., Indirect measurement Quantity not measured directly. The quantity to be measured with calculations. Measuring angle with sine bar is the example of indirect measurement. Some of indirect measurement instruments are sine bar. Contact measurement In this measurement, instrument’s tip makes contact with the surface being measured. Example : Vernier caliper, micrometer and dial indicator. Non contact measurement In this measurement, there is no contact between the measuring tip and measuring surface. Example: tool maker’s microscope , comparators and optical measurements Primary, secondary and tertiary measurement In primary measurement, the quantity to be measured directly by