From QB64.org wiki
The <> condition symbol denotes that a value must not equal another value for the condition to be True.
Example usage: IF x <> 320 THEN PRINT "Not in center of screen"
- Statements will evaluate as True or -1 when two values are not equal or False or 0 when equal.
- More than one <> symbol in a numerical statement will create a Boolean evaluation of the ensuing numerical pairs.