Previously when we discussed the packaging process, I've mentioned that it happens in different phases, and one of those phases is called cooking the content. When it comes to packaging a game, Unreal is very smart and they thinks about how to make the best of your time as a developer.

Let's assume that you have made a huge game, about 10 GB in size. What if you have changed a single texture? Do you have to build the whole thing in order to test it? Or do you have to build the whole thing in order to publish it?

Unreal does a good separation between the game logic and its content, and as long as you want to rebuild the content itself, you can always do it by cooking. Content such as textures or sound files always have their own file formats, like PNG, JPG, WAV, or MP3, but when you package the game, you never find those files, as the engine works on converting those files to more encrypted and engine-friendly formats that match the targeted platforms. And that's called...