What is difference between png8 and png24

Question

I want to know about uses of png files. There are two formats available for png images; one is png8 and the another one is png24.

Answer 1

While making image with fully transparent background in PNG-8, the outline of the image looks prominent with little white bits. But in PNG-24 the outline is gone and looks perfect. Transparency in PNG-24 is greater and cleaner than PNG-8.

PNG-8 contains 256 colors, while PNG-24 contains 16 million colors.

File size is almost double in PNG-24 than PNG-8.