God is “the Supreme Being; the Creator and Ruler of all that is; the Self-existent One who is perfect in power, goodness, and wisdom.” -See Who is God? (GotQuestions)
God: Creator, Judge, Redeemer
God is a Trinity
The God of the Bible is a Trinity. He is one eternal God existing in three distinct, simultaneous persons. There are not three Gods; there is only one God. The Bible teaches that the Father is God, Jesus (the Son) is God, and the Holy Spirit is God -- one God, three persons.
The triune nature of God is hard for the finite mind of man to fully comprehend, but it is essential to understanding who God is.
God Is Triune by Henry M. Morris III, D.Min. (ICR)