Chevalley group of type G2

Definition
Let $$K$$ be a field.

The Chevalley group of type $$G_2$$ over $$K$$, denoted $$G_2(K)$$, is defined as the group corresponding to the Dynkin diagram:



For a prime power $$q$$, $$G_2(q)$$ is defined as the group $$G_2(\mathbb{F}_q)$$.