Delegation is just sending a certain amount of your token to another account.
First, the person who sends it might be doing it as a selfless act (e.g.those who delegate HP to Newbies to help them navigate Hive without hitches for a while)
Second, the person who sends it might want some returns. I have seen projects that requires one to delegate a portion of their tokens for reblogs, post upvotes, and yes, rewards, (rewards could be liquid hive, or other hive engine tokens)
This is the only two uses of delegation that I know of. I hope it helps you, if it doesn't, I'll explain with all my understanding, so, go on, and ask questions
Thank you)) Yes, this is what I also learnt today. I just didn't know that was what it meant all this time and was excited to know I could delegate with the resources I already had. Makes me more commited to keeping up here.