What is the meaning of: "Allah in His essence is Light"? Does this mean that Allah is made of light?

Allah Almighty is Light by His Essence, but "there is nothing like unto Him." The texts refer to the Lord as Light, and attribute a light to Him, and describe Him as the Light of the heavens and the earth, and state that His veil is light. The light of Allah may be attributed to His Face or to His Essence.