Well, instead of going deeper into the concepts, I would present the basic descriptions of the two
A company may decide to offer additional shares to the share holder. When a company plans to provide a bonus share of 1:2, it would mean you will get two shares for every single share you have. If you have 100 shares of a company, a 1:2 bonus share will give you 200 shares more which would mean you now hold 300 shares.
This move is a means of helping out in liquidity of the shares. If stocks are split in the ratio 1:2, one share you hold will be treated as two. That would mean if you have 100 shares of Rs. 100 each, a stock split at 1:2 will mean you now hold 200 shares at Rs. 50 face value. The net share worth remains same at Rs. 10000 itself.
Having described them, let us now come to the difference. Either of them do not change your share value. Your earnings per share will remain the same. A stock split will make the shares affordable for the smaller shareholders. Thus, the company can look forward to an increased demand for the shares. Bonus will improve your market value.
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