Answer
A compound statement that is always true is called a tautology. A compound statement that is always false is called a self-contradiction.
Example:
For example, consider the truth table for \[\left( p\wedge q \right)\to \left( p\vee q \right)\] as shown below:
The last column of the truth table is always true, hence the statement \[\left( p\wedge q \right)\to \left( p\vee q \right)\] is a tautology.
