Fact behind the Gap-up and Gap-down

Dear All,

Pls anyone explain me , why does gaps are created in any asset class and the reason behing the same.

Ex : on 02 march Nifty future opened with 100 pts gap up

A gap is a change in price levels between the close and open of two consecutive days.The traders expect price may fall or rise based on their assumptions, so they they put price above market when hoping market may go up or sell at lower price when expecting that prices may fall.