Texture: The size, shape, and position of the grains which the rock is made of (Can use the terms, fine-grained, medium-grained, and coarse-grained to describe texture).

Intrusive Igneous Rock: Formed from magma that cools (in-ground).

Extrusive Igneous Rock: Formed from lava that cools.
Felsic: Describes relatively light-colored, light weight igneous rock.

Mafic: Describes relatively dark-colored, heavy igneous rock.

Composition: Describes what minerals a rock is made of.

Strata: Layers that form in sedimentary rock (most noticeable feature of a sedimentary rock.)

Stratification: The layering of sedimentary rock (i.e. The process of the layers being made).

Clastic Sedimentary Rock: Made of fragments of other rocks and minerals.

Chemical Sedimentary Rock: Forms from solutions of minerals in water.

Organic Sedimentary Rock: Formed by the remains of dead animals.