# Definition:Disjunction/Notational Variants

## Definition

Various symbols are encountered that denote the concept of disjunction:

Symbol Origin Known as
$p \lor q$ 1910: Alfred North Whitehead and Bertrand Russell: Principia Mathematica vee or vel
$p\ \mathsf{OR} \ q$
$p \mathop \| q$ Used in various computer programming languages
$p + q$
$\operatorname A p q$ Łukasiewicz's Polish notation