What is demodulation ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Modulation**:
- Modulation is the process of varying a carrier wave in order to transmit information such as music or speech. Low-frequency signals (like audio signals) cannot travel long distances effectively, so they are combined with high-frequency carrier waves.

2. **Definition of Demodulation**:
- Demodulation is the reverse process of modulation. It involves extracting the original information signal from the modulated carrier wave.

...