Question

Difference between than and then?

Answer 1

then relates to time.............
than relates to a comparison.........

Answer 2

Than - mostly used for comparison. For eg. : He is stronger than Rivan.
Then - mostly used to denote a period of time (or a consequent action)
         For eg. : He used to be really kind back then. 
        For eg. :  Then he picked up the stone and threw it. 
However, in English, every word can be used in a number of ways, provided it is grammatically correct.