3 Input OR Gate
A 3-input OR gate has three inputs, A, B, and C, and one output Y. The output is HIGH (1) when at least one input is HIGH (1). The output is LOW (0) only when all three inputs are LOW (0).

3-Input OR Gate Symbol

3-Input OR Gate Boolean Expression

3-Input OR Gate Truth Table

In simple words: A 3-input OR gate produces 0 only when A, B, and C are all 0. In every other combination, the output is 1.