I'm doing an assignment for school and I can't find the answer to my question anywhere! I'm making a logo for a game that I have designed, it's the most frustrating thing ever! If you know, please tell me asap.
You can "flatten" your image using a program like gimp.
Every raster format support non transparent images, but only few does support transparency.
The transparency on a png file is an aditional channel, this is, you have your rgb image (a simple graph or photo) and besides that you have one more channel that you can use or not. In that channel you can have some parts in black and some in white or inclusive you can have a complete grayscale photo.
Some other raster formats like gif only support one very specific color in its pallete as transparent For example an exact green. If you have a simmilar green next to it it wont be transparent.