In ample measure, one of the mostly searched topics arises in the mind of each individual whenever meets at the time of internet use. It is the description of bandwidth & what is the data rate at the same time.

Generally, data rate comes along with it & produces another question to answer. We have tried to familiarise you with this context in detail.
Before describing Bandwidth, you need to hold your patience a bit little. You'll not be able to understand the fact completely without having the idea about computer's language.
The computer uses or understands the only Binary system. It shows & does everything in this Binary language starting from solving math to data transmission. The data transmission rate uses high & low frequency. Here, high frequency means 1 & low frequency means 0.
If you are studying about the computer, you'll have the idea that a lot of definitions are there about Bandwidth. We provide the one which worths understanding in a broader aspect.

Bandwidth: It is defined as the amount of data(as frequency or wavelength) transmitted through wired or wireless network (internet connection) at maximum or minimum rate. 

  1. Bandwidth is the transmission of data in the form of a signal or electromagnetic pulse.
  2. The signal cannot exceed the Bandwidth rate.
  3. The high pulse is 1 & low pulse is 0.
  4. Bandwidth unit is measured in HRZ (herz).
*Another notion is that Bandwidth is the data, transmitted per unit time. i.e. data/time. The data transmission rate is BPS (Bits Per Second) or MBPS (Megabit Per second).

Data rate: It means the quantity or measurement of data passes through a medium or band.

The small amount of data passes through when bandwidth is low or small.
And, if the Bandwidth is increased, more data can pass i.e. uploading & downloading speed rate per second. 

What is the connection Between Bandwidth & Data rate?

It is expected that from reading this context from the starting, you have got a general idea about what is Bandwidth & What is Datarate. 
Example
  1. To be more specific if you take a small pipe for example. And, you pass some water through that pipe. The quantity of water passes through that pipe is similar to the data rate. And, the size of the pipe is bandwidth. 
  2. Larger the width of that pipe is, much the amount of water flows via that pipe. 
  3. However, sometimes the amount of water flowing can be lower in spite of being a large pipe. 
  4. Similarly, our internet speed sometimes decreases although we use a mammoth size of bandwidth.
*The data rate is always proportional to bandwidth but bandwidth not. As for example, the data rate can not exceed the bandwidth limitation or it can't overflow the actual bandwidth.