1+1 is a mathematical expression that evaluates to:

  • 2 (number) (in ordinary arithmetic)
  • 1 (number) (in Boolean algebra with a notation where '+' denotes a logical disjunction)
  • 0 (number) (in Boolean algebra with a notation where '+' denotes 'exclusive or' operation, or in a quotient ring of numbers modulo 2)

The terms 1+1, One Plus One, or One and One may refer to:

1+1

One Plus One

One and One

Other

See also