God is a relational being, existing in three persons that relate to each other perfectly. He created mankind in his image, and this includes our capacity and the need for relationships. Prayer is a gift to us, for it is our way to connect with God and have a relationsihp with Him. Yes, God knows what will happen in the future. But because He wants a relationship with us, it pleases Him to hear us ask for what we desire.

Also, prayer isn't just about asking for things. It is also meant to be our way of expressing to God our adoration of Him and our thanksgiving for what He has done, and provides the means to ask for His forgiveness.

Gahalia