A stock split is a corporate action through which the company increases the number of shares its investors hold by dividing each existing share into multiple shares. As a result, the price of each share decreases proportionately, while the total value of your investment remains the same. 

For example, in a 1:2 stock split, every 1 share becomes 2 shares. Here's what happens when a company announces a 1:2 stock split: 

If you owned 100 shares priced at ₹200 each before the split, you would own 200 shares priced at ₹100 each after the split. The total value of your investment would still be ₹20,000 – so you don’t really gain or lose anything after the split.