Granite forms when bits of quartz and feldspar are pushed up out of the liquid rock beneath the earth's crust, so it's one kind of igneous rock. The word "granite" comes from the Latin word "granum", a grain, because granite is made of lots of smaller bits of quartz and feldspar stuck together (think of our word "granary", a place where you store grain). Granite comes in different colors, usually pink to gray or sometimes black.
Granite's a very hard stone. It's hard because it formed as hot liquid stone, and so the molecules inside it are all jumbled up any which way, instead of lying in layers as in sedimentary rocks like limestone or slate.
Because granite is so hard, people sometimes use it for building stone or statues if you want them to last a long time. But granite is so hard that it's also hard to cut into blocks or statues. In ancient Egypt, sculptors used granite to carve statues of pharaohs. People today often use granite for kitchen countertops, too.
To find out more about rocks, check out these books from Amazon.com or from your library:
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