Commitment scheme

In cryptography, a commitment scheme is a way for a person to give out a piece of information without letting other people know what that information is. The reason a person would do this is so that they can make sure they can prove who they are, or make sure that someone doesn't cheat. The way it is usually done is by using a one-way function to change a string into a hash. This is called the 'commit phase'. Afterward, if someone needs to prove that they were the one who made the commitment, then they can tell people the original string they used. This is called the 'reveal phase'.