What is the difference between by-election and mid term election?
Mid term Election---When elections are held much before the schedule, it is considered as the "Mid-term Election". The President can dissolve Lok Sabha and call a general election before five years is up, if the government can no longer command the confidence of the Lok Sabha, and if there is no alternative government available to take over.
Bye-election-- A special election to fill a vacant elective position with an unexpired term due to demise or resignation of the occupant.
I think you mean difference b/w General and By-elections.
General elections-After five years the term of all elected representatives comes to an end.The Lok Sabha or Vidhan Sabha stands 'dissolved'.Elections are held in all constituencies at the same time , either on the same day or within a few days .This is called a general election .
By-elecions - Sometimes election is held only for one constituency to fill the vacancy caused by death or resignation of a member.This is called By-elections.