1)      Sliding pair- when the two elements of a pair are connected in such a way that one element can slide relative to the other. Example- the piston and cylinder, tail stock on lathe bed.

2)      Turning pair- when the two elements of a pair are connected in such a way that one element can revolve about a fixed axis of another link. Example- lathe spindle supported on head stock.

3)      Rolling pair- when the two elements of a pair are connected in such a way that one can roll over another fixed link. Example- ball and roller bearings.

4)      Screw pair- when the two elements of a pair are connected in such a way that one element can turn about the other by screw threads. Example- nut and bolt.

5)      Spherical pair- when the two elements of a pair are connected in such a way that one element can turn about the other fixed element. Example- ball socket joint.

6)      Lower pair- when the two elements of a pair have surface contact when relative motion takes place and the surface of one element slides over the surface of the other element. Example- sliding, turning and screw pairs.

7)      Higher pair- when the two elements of a pair have a line or point contact when relative motion takes palace and the motion between the two elements is partly turning and partly sliding. Example- toothed gearing.