Answer for Share Split vs Bonus

Both are very similar, and have almost the same effect, except for Par Value.
 
In Bonus Issue, the Par Value remains the same, but in Stock Split, the Par Value changes proportionately. For example, a stock split of existing 1 share to 2 shares will reduce the company’s Par Value by half.
A good write up is here: http://stockresearchasia.com/stock-split-vs-bonus-issue.html