Different Geometric Forms Straightness Flatness Circularity Parallelism Squreness
Straightness A line is said to be straight over a given length if its deviation with respect to ideal reference line are within the specific tolerance limit
Test for Straightness Using the straight edge Wedge Use method of spirit level
Flatness It is defined as minimum distance between two planes within which all the points on a surface lie. A surface along which all the points lie along single plane is called as perfectly flat surface.
Test for Flatness Using a surface plate Straight edge Dial gauge Spirit level Autocollimator Interference method
Squareness Checking of squareness or squareness testing implies checking weather the one plane is right angle to another.
Test for Squareness Try square Combination square Indicator method Autocollimator
Parallelism Two line axis or plane are said to be parallel two each other if the distance measure between them in a perpendicular plane remain same.