The basic principle behind the computers is . . . . .

Answer

### Step-by-Step Solution:

1. **Understanding Computers**:
- Computers are electronic devices that process information. They operate on specific principles that allow them to perform tasks and solve problems.

2. **Binary System**:
- The fundamental principle behind computers is their ability to understand the binary system. The binary system consists of two digits: 0 and 1. This is the language that computers use to process data.

3. **Digital Logic**:
- Computers utilize digital logic to interpret binary data. Digital logic involves using binary values to represent logical statements. In this context, "1" typically represents "true" or "yes," while "0" represents "false" or "no."

4. **On-Off Circuits**:
- The digital logic is implemented through on-off circuits, which are controlled by transistors. These circuits can be in one of two states: on (1) or off (0). This binary state allows computers to perform complex calculations and operations.

5. **Conclusion**:
- Therefore, the basic principle behind computers is the use of binary code and digital logic, which allows them to process information and execute commands based on logical operations.

### Final Answer:
The basic principle behind computers is the use of binary code and digital logic.

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