An asset that is held for a period of 36 months or less is a short-term capital asset. The criteria of 36 months have been reduced to 24 months for immovable properties such as land, building and house property from FY 2017-18.
For instance, if you sell house property after holding it for a period of 24 months, any income arising will be treated as long-term capital gain provided that property is sold after 31st March 2017.
An asset that is held for more than 36 months is a long-term capital asset. The reduced period of the aforementioned 24 months is not applicable to a movable property such as jewelry, debt-oriented mutual funds etc. They will be classified as a long-term capital asset if held for more than 36 months as earlier.