# Analog and Digital

Analog and digital are the terms that we often referred with data and signals. In today’s discussion we will be talking about both analog and digital data, and analog and digital signals.

If we say that there is a sender who has some data to be transmitted to the receiver. But the data that is understandable by a person or an application cannot be transmitted as it is on the transmission network. It has to be first converted into signals so that we can transmit it over the network.

Let us take an example you have to send an image to the receiver. The image first has to be changed to a form that the transmission network can accept. Now the transmission media accepts signals and transmits it’s over the physical path.

## Analog and Digital

### Analog and Digital Data

Data can be in both the forms analog as well as digital. The analogous data is continuous and the digital data is discrete. As digital data is discrete it can be counted and has a finite value.

We have a popular example with which we can understand the difference between analog and digital data easily. You all must have the analog clock that is comprised of a minute hand, a second hand, and an hour’s hand. All the hands of the clock keep on rotating continuously and keep on giving continuous information.

Example1:

You also might have come across the digital clock. The digital clock reports you whenever a second, minute or hours changes i.e., it will report you if 8:30 changes to 8:31.

Example 2:

Now whenever a person speaks it generates continuous data which we can refer to as analog data. This analog data forms an analog wave in the air. This analog wave can be captured by the microphone where it can be converted to the analog signal. This analog signal can be sampled and converted to a digital signal.

Example 3:

The digital data is always in a discrete form such as the data in the computer is stored in the form of 0s and 1s. this digital data can be converted to a digital signal which can be further modulated to form an analog signal which is convenient to transmit over the transmission medium.

### Analog and Digital Signal

Like data, signals can also be analog or digital. An Analog signal can present an infinite number of values within a specified range. However, the digital data presents only limited valued and the values can be defined easily.

To represent a signal may it be analog or digital we can plot them on the pair of the perpendicular axis. The vertical axis is used to represent the strength of the signal and the horizontal axis is used to represent the range of the time over which the signal is represented. Observing the figure above we can see both the analog and the digital signals. The curved signal that represents infinite values is the analog signal and the vertical lines that represent the sudden change of the values represent the digital signal.

### Periodic and Non-Periodic Signals

• Analog and digital signals can be further classified into periodic as well as non-periodic signals:
• A periodic signal is a signal that repeats itself after a particular time interval. The periodic signal forms a specific pattern.
• The periodic signal can be further classified into simple and composite signals.
• The simple signal cannot be decomposed into simpler signals.
• The composite signal can be decomposed into simpler signals.
• The non-periodic signal does not repeat itself after a particular time interval and it does not form a specific pattern.

In this context, we have discussed data and signals. We have seen both data and signal can be analog and digital. We have also discussed the example of analog and digital data and signals.

Further, we have seen that the analog and digital signals can be either periodic and digital. The periodic signal can be simple as well as concept. To transfer the data over the transmission medium we need to convert it into signals.