As is clear from the name itself, bit rate is the rate at which bits are transferred from one location to another. In simple terms, it is used to measure the quantum of data transmitted in a specific time frame. Bit rate is generally measured in bits per second (bps) but it is not uncommon to express bit rate in kilobits per second (Kbps), or megabits per second (Mbps).
Bit rate can affect the image and video quality of your content. A higher bit rate will have room for higher image quality in the video output. There is something called variable bit rate (VBR) encoding will produce better image quality than constant bit rate (CBR) in most applications. The key benefit of VBR encoding is that it can assign higher bit rate to the more multifaceted segments of your media files and allocate lower bit rates to the undemanding segments.