Essential elements of a communication system are

Explanation

### Step-by-Step Solution

1. **Identify the Components of a Communication System**: A communication system is fundamentally composed of three essential elements: the transmitter, the channel, and the receiver.

2. **Transmitter**: The transmitter is the first element in the communication system. Its primary function is to convert the original message signal (which can be in various forms such as audio, video, or data) into an electrical signal. This conversion is crucial as it allows the signal to be transmitted over a medium.

3. **Channel**: The second element is the channel. The channel is the medium through which the electrical signal travels from the transmitter to the receiver. This medium can be physical (like cables) or wireless (like air for radio waves). It is important to note that during transmission, the signal may encounter noise, which is an unwanted signal that can interfere with the original message.

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