First off, The Trinity is the holy three for christians. Since God is eternal and all powerful, H e can take on any form He wants. That's where the Trinity comes in. First there is God the Father. He created the world, talked to Moses, and lead the world through prophets and kings. Then there is God the Son, also known as Jesus. Jesus is the Son of God, and is said to be God with flesh on. He left his throne in Heaven to die a gruesome death on the cross so we could be forgiven of our sins. Then there is God the Holy Spirit. He came down to help us in a dark world. He makes sure we follow God's path. It's important to Christians because it embodies everything we believe in: God the Father, God the Son, and God the Holy Spirit. I hope this helps and isn't too confusing. It's a strange concept to wrap your head around and I'm a christian.