A capital gain arises when you sell a capital asset for more than its purchase price. Capital assets include listed equity shares, mutual fund units, real estate, gold, and bonds. The gain is the difference between the sale price and the cost of acquisition. That gain is then classified as short-term or long-term based on how long you held the asset before selling.
The classification matters because STCG and LTCG are taxed at different rates. And critically, the holding period threshold is not the same across all assets.

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