What do you mean by modulation ? What are its types ?

Explanation

### Step-by-Step Solution:

**Step 1: Definition of Modulation**
Modulation is the process of varying one or more properties of a carrier wave in accordance with the information signal that is to be transmitted. In communication systems, modulation allows low-frequency signals (such as audio signals) to be superimposed on high-frequency carrier waves, enabling them to be transmitted over long distances.

**Step 2: Purpose of Modulation**
The main purpose of modulation is to enable the transmission of signals over long distances. Low-frequency signals, such as music or speech, cannot travel long distances effectively. By modulating these signals onto a higher frequency carrier wave, they can be transmitted more efficiently.

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