How does iCloud backup work?

I got to the point where my iPhone is backing up to the cloud. I have backed up a batman games because I've gotten really far and don't want to lose the save data but its taking up a lot of space on my phone. If I delete it off of my phone will the save game remain in iCloud? Will I be able to redownload the game and use that same data?

Icloud is good, I usually just tap backup manually when I want to do it, but you can also sign on to www.icloud.com and it will show you what you have backed up… Pretty slick.