User:Penguin-Pal/GIMP

Creating Alpha channel
Color models such as RGB, HSL, and HSV have 16,581,375 different displayable colors (!!!). Alpha Channel, if added, gives the ability to add opacity to images, which is quite helpful if you don't want a background for your image, or would like to paste this image later above another image.

You can add Alpha Channel by right-clicking anywhere in your file, going to Layer → Transparency → Add alpha channel.

If your image has already had background behind it (like a screenshot), you can then select it using the Fuzzy select tool (or by pressing A), selecting the background by clicking it, and then press Delete.