More generally, one speaks of an additive group whenever the group operation is notated as addition; in this case, the identity is typically denoted ⁠ 0 ⁠, and the inverse of an element x is denoted ⁠ − − x ⁠. Similarly, one speaks of a multiplicative group whenever the group operation is notated as multiplication; in this case, the identity is typically denoted ⁠ 1 ⁠, and the inverse of an element x is denoted ⁠ x − − 1 ⁠. In a multiplicative group, the operation symbol is usually omitted entirely, so that the operation is denoted by juxtaposition, a b instead of ⁠ a ⋅ ⋅ b ⁠.