The Exclusive-OR function is one of the most useful of the special logic functions. The Exclusive-OR is sometimes also called the "Either/OR but not Both" function. With only two inputs, the output is true if either of the inputs is true but not both of the inputs. Another way to say this is that the output is true if both of the inputs are the opposite of each other.
Although the Exclusive-OR is a special function, it is most convenient to use the Exclusive-OR in its SOP form (). Although the special symbol Å can be used to identify the Exclusive-OR, there are no rules in the Boolean Algebra to deal with this special formula. If the Exclusive-OR symbol is encountered in a Boolean Expression, it should be converted to its SOP form before any reduction process is started.