Name two gates which can be used repeatedly to produce all the basic or complsicated gates.

Explanation

To answer the question, we will identify two gates that can be used repeatedly to produce all the basic and complicated logic gates.

### Step-by-Step Solution:

1. **Identify Universal Gates**:
- The two gates that can be used to produce all other gates are the **NAND gate** and the **NOR gate**. These gates are known as universal gates.

2. **Understanding NAND Gate**:
- The NAND gate can be used to create the basic gates:
- **NOT Gate**: By connecting both inputs of the NAND gate to the same input (A), the output will be the NOT of A (i.e., A').
- **AND Gate**: To create an AND gate using NAND, you can take the output of a NAND gate and connect it to a NOT gate (which can be made using another NAND gate).
- **OR Gate**: To create an OR gate, you can use two NAND gates to invert the inputs and then connect them to another NAND gate.

3. **Understanding NOR Gate**:
- The NOR gate can also be used to create the basic gates:
- **NOT Gate**: Similar to NAND, by connecting both inputs of the NOR gate to the same input (A), the output will be the NOT of A (i.e., A').
- **OR Gate**: By connecting the outputs of two NOR gates to another NOR gate, you can create an OR gate.
- **AND Gate**: To create an AND gate using NOR, you can take the output of a NOR gate and connect it to a NOT gate.

4. **Conclusion**:
- Therefore, both the NAND gate and the NOR gate are capable of generating all basic and complicated logic gates, making them fundamental components in digital electronics.

### Final Answer:
The two gates that can be used repeatedly to produce all the basic or complicated gates are the **NAND gate** and the **NOR gate**.