here are the 3 image types well use

PNG

PNG or (Portable Network Graphics) is a recently introduced format, so not everyone familiar with it. But PNG has been approved as a standard since 1996. It is an image format specifically designed for the web. PNG is, in all aspects, the superior version of the GIF. Just like the GIF format, the PNG is saved with 256 colors maximum but it saves the color information more efficiently. It also supports an 8 bit transparency.

PNG was actually created for the intent to replace the GIF as an image format that doesn't require a patent license. PNG can support 24 bit RGB color images, grayscale images, both with and without alpha channels. RGB cannot support CMYK color spaces, and is not designed for print graphics.

Pros

• Lossless, so it does not lose quality and detail after image compression
• In a lot ways better then GIF. To start, PNG often creates smaller file sizes than GIF
• Supports transparency better than GIF

Cons

• Not good for large images because they tend to generate a very large file, sometimes creating larger files than JPEG.
• Unlike GIF however, it cannot be animated.
• Not all web browsers can support PNG.