Proof techniques are methods used in mathematics and logic to establish the truth of statements or theorems. Common techniques include direct proof, where a statement is proven by straightforward logical reasoning, and indirect proof, which involves assuming the opposite of what you want to prove and showing that this leads to a contradiction. Another important technique is mathematical induction, often used for proving statements about natural numbers. This method involves two steps: proving the base case (usually for the number 1) and then showing that if the statement holds for an arbitrary number, it also holds for the next number.