What is igneous rock made of

Igneous rock forms from magma, which is molten rock, cools on the surface of the Earth.

So they are made of magma which has cooled.

A good example of intrusive igneous rock is granite. Extrusive igneous rocks form when the magma or molten rock pours out onto the earth's surface or erupts at the earth's surface from a volcano. Extrusive rocks are also called volcanic rocks. Basalt, formed from hardened lava, is the most common extrusive rock