Kilobit is a unit of digital information abbreviated as ‘kb’ with a lowercase ‘b’ to prevent confusing it with the term byte, which is abbreviated with an uppercase ‘B’.
The kilobit is equivalent to 1000 bits or 125 bytes (1000 bits divided by 8 bits per byte).
The term kilobit is most usually used in measuring data transfer speed or network transmission speed. Most Internet connections are now measured in megabits (Mb) rather than kilobits. But originally, to access the Internet people would use dial-up connections via computer modems. The speeds for these modems were on the order of kilobits per second. Some examples are 1.2kbps in the mid to late 1980s, 2.4 kbps, 28.8 kbps and finally 56kbps in the late 1990s.
The average broadband connection speed in the UK in 2013 was 14.7 Mbps. When compared to the 56kbps modems, the average connection speed in 2013 is over 261 times faster.
It is this type of massive improvement in the ability to transmit data over the Internet that has given rise to streaming movies, videos, interactive games, audio and large file downloads such as HD movies.
A more common use of kilobit today is in reference to audio file sizes and quality. If you listen or download mp3 files you’ll probably notice you can often choose 192 kbps, 160 kbps, 128 kbps or even 96 kbps. The higher the number of kilobits per second (kbps) you choose, the better the sound quality of the file. The higher number also means larger file sizes which impacts the bandwidth you’ll use streaming these files on the Internet, or the amount of space they will take up on your mp3 player.