Distribution is a rule of inference used in propositional logic. Also written as 'Dist.' for short. It goes like this:
{P∧(Q∨R)} = {(P∧Q)∨(P∧R)}
And
{P∨(Q∧R)} = {(P∨Q)∧(P∨R)}
Or in English: "P and either Q or R" is the same as "either P and Q or P and R" and "either P or Q, and also R" is the same as "either P or Q and also either P or R". If you think about it, it really does make sense, but you may find it useful to make a truth table.
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