A stock split is when a company increases the number of its outstanding by issuing more shares to current shareholders, while the face value of the stock decreases. The ratio by which stocks get split is decided by the company in the AGM/EGM after approval from the board of directors and shareholders. 

In a stock split, the number of outstanding shares increases and the price per decreases proportionally. As the per-share price is lower, they’re more affordable. 

The value of the company does not change after a stock split.