Data Rate
The speed at which data is transferred, as in bytes per second. Also called bit rate.
For example, the speed to download or stream a video file over the Internet, or the speed at which the file must play from a hard disk. When you create a video or audio file, you can specify the target bit rate at which the file will be played.
Data Transfer Rate:
It is the number of bits or bytes that pass in one second during the transmission of a data in the network or internet environment between two points. In other words, the more bits or bytes transmitted per second, the higher the data transfer rate. Data transfer rate is measured in kilobits, megabits, gigabits, terabits or kilobytes, megabytes, gigabytes, terabytes.
The abbreviations mbps (mb/second) or mBps (mB/second) are used to express data transferred in one second.