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What is data, information and signal ( any confusion about their difference ! )

[What is Data?]
Data are simply values or sets of values of qualitative or quantitative variables, belonging to a set of items. It may be in the form of numbers, letters, or a set of characters. It is often collected via measurements. In data computing or data processing, data is represented by in a structure, such as tabular data, data tree, a data graph, etc.

difference between data and information

[What is Information?]
Once the data is analyzed, it is considered as information. In other words, meaningful or processed data is known as information. Example- Suppose we have a collection of numbers like 23, 25, 87 etc. These can be called as data. Now if we specified these numbers with an attribute like ID of some people in a system then they call information. Because this time each number represents a user identity.

What is signal

[What is signal?]
In communication or electronic system we need to transfer information. And that is happened electrically.  In order for data or information to be transferred electronically, it must first be converted into electromagnetic signals. The signal can then be used to transfer data from one device to another device. The signal can be either analog or digital in nature. The analog signal refers to a continuous stream of data, whereas digital signal converts the data into discrete states as discus in a post before. But remember that all the part of the signal don't contain information. That is why we can say that some portion of signal convey or is data.

Hence, data and signal are two completely different things. Data is a collection of values in any form . Signal, on the other hand, is used to transfer this data from one point to another.
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Different types of noises & signals in communication sustem

What is Noise?  
The noise is the unwanted signals that tend to disturb the operation of a system and over which we have incomplete control.

Two broadly used categories of noise are given below:

External noises: The noise whose sources are external to the communication system is known as external noise. Example- atmospheric noises, extraterrestrial noises, man-made noises etc.

Internal noises: The noise which get generated within the communication system is known as internal noise. Example- shot noise, thermal noise, transit-time noise, miscellaneous internal noises etc.       


Signal: A signal is formally defined as a function of one or more variables that conveys information on the nature of a physical phenomenon.


Several types of signal’s are given below-

Continuous-time signal:- A signal that is specified for every value of time is a continuous time signal. Example- telephone and video camera output.

Discrete-time signal:- A signal that is specified for only discrete values of time, is a discrete-time signal. Example- monthly sales of a corporation.

Analog signal:- A signal whose amplitude can take on any value in a continuous range is an analog signal.

Digital signal:- A signal whose amplitude can take on only a finite number of values is known as digital signal.

Periodic signal and aperiodic signal:- A signal g(t) is said to be periodic if for some positive constant T0 ,
                                              g(t) = g(t + T0 )
The smallest value of T0 is the period of g(t). A signal is aperiodic if it is not periodic.

Deterministic signal:- A signal whose physical description is known in either a mathematical form or a graphical form is a deterministic signal.

Random signal:-A signal which is known in terms of probabilistic description such as mean value, mean squared value and so on rather than its complete mathematical or graphical description is a random signal.

Energy signal:- A signal with finite energy is an energy signal. In other words, a signal g(t) is an energy signal if 
Power signal:- A signal with finite power is a power signal. In other words, a signal g(t) is a power signal if
Causal signal:- A signal that does not start before  t=0 is called a causal signal.
                                           g(t) = 0            , t<0 span=""> 

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