A full adder has **three inputs**:
1. **A** - The first binary input.
2. **B** - The second binary input.
3. **Cin (Carry-in)** - The carry input from the previous less significant bit (if any).
In addition to these three inputs, the full adder also has two outputs:
1. **Sum (S)** - The sum of the two inputs (A and B), considering any carry input (Cin).
2. **Carry-out (Cout)** - The carry output, which is generated when the sum exceeds the value that can be represented by a single bit (i.e., when the sum is 2 or greater).
The full adder can be described using the following logical equations for **Sum** and **Carry-out**:
- **Sum = A ⊕ B ⊕ Cin** (where ⊕ is the XOR operation)
- **Carry-out (Cout) = (A AND B) OR (Cin AND (A XOR B))**
This allows the full adder to add two binary numbers along with any carry from the previous bit.