Gem,

Both are spiritual "gifts" or charisms that are listed in First Corinthians 12.

Word of knowledge is what it sounds like. A person without any natural knowledge of a situation may be given knowledge of it by the Holy Spirit.

Prophecy is simply saying what God would have you say and speak, in His name. Most people think of prophecy in terms of some kind of prediction but it's actually not the same.

Isaiah 55 tells us that the Word of God does not return void once it is spoken. Hence, prophecy
is not predicting the future, rather it is bringing it to pass. It is simply speaking in the name of God, for example, if the Holy Spirit leads someone to go tell another "Jesus loves you," then the person is speaking prophetically.

John