In general, operators describes how filter conditions are linked together. The following operators can be used.
AND
All filters placed below must be true. Only then AND returns true.
OR
Even if one of the filter placed below OR is true, OR returns true.
NOT
Only one Filter can be placed below NOT operator, and if the filter evaluation is true, NOT returns false.
XOR
Only one of the two filters are possible in the XOR Operator.
TRUE
Useful for debugging, just returns TRUE.
FALSE
Useful for debugging as well, returns FALSE.