A right angle bracket delimiter commonly used in mathematical notation for inner products, bra-ket notation, and sequence elements.
Examples
Inner product (bra-ket) notation in quantum mechanics
\langle \psi | \phi \rangle = \int \psi^*(x) \phi(x) dx
Vector inner product
\langle u, v \rangle = \sum_{i=1}^n u_i v_i
Set builder notation with angle brackets
\langle x, y \rangle \in \mathbb{R}^2 : x^2 + y^2 = 1