# Booleans

The type `sp.bool`

has two literals: `True`

and `False`

The expression `a and b`

is `True`

if and only if *both* `a`

and `b`

are `True`

. The expression `a or b`

is `True`

if and only if *at least one* of `a`

and `b`

is `True`

. The expression `a ^ b`

is `True`

if and only if *exactly one* of `a`

and `b`

is `True`

.

Note that `and`

and `or`

do "short-circuiting": for `a or b`

, if `a == True`

then `b`

is not evaluated. For `a and b`

, if `a == False`

then `b`

is not evaluated.

For example, this statement runs successfully:

smartpy

`assert True or 1 / 0 == 42`

On the other hand the following statement raises a division-by-zero error:

smartpy

`assert 1 / 0 == 42 or True`

Note that these operations work on booleans only. For bitwise operations on integers, see bitwise arithmetic.