Orthogonal Basis

A basis where each vector is orthogonal to to every other vector.

Let $W$ be a subspace of ${\mathbb{R}}^n$ and has an orthogonal basis formed by vectors: $\overrightarrow{u_1},...\overrightarrow{u_p}$ $\forall (\overrightarrow{u_i}\in W),\forall (\overrightarrow{u_j}\in W)((i\ne j)⟹(\overrightarrow{u_i}\cdot \overrightarrow{u_j}=0))$

See Orthonormal Basis