Following Dallas Willard I'm defining prayer as: talking with God about what we (God and I) are doing together. In prayer, we converse with the King of heaven and earth.
Every Jesus-follower is on The Mission of Redemption with God. Mixing headship metaphors, God is our Shepherd, God is our King. The New Testament's Big Idea is that our King died, was raised, and now lives to build his kingdom people on earth, as it is in heaven. In prayer with God we learn how to build lasting things.
This is a privilege, as Wayne Grudem writes:
God wants us to pray because it allows us to be a part of a story that is greater than our own. It allows us to be involved in activities that have eternal significance. When we pray, God’s kingdom is advanced as his will is done “on earth as it is in heaven” (Matt. 6: 10). (Grudem, Christian Beliefs: Twenty Basics Every Christian Should Know, Kindle Locations 600-602)
Prayer is involvement in His-Story. That's what's happening as you pray today.