Kilobits or Kilobytes

So sometimes that odd question from nowhere hits you and you have to explain the difference between the concepts to someone.  What is the difference between kilobit and kilobyte?

The question was not posed based on “how many” of what makes what but why you would use one over the other in measurements of delivery capabilities.

The easiest way to approach this is that a kilobit (kbps – kilobits per second) is a measure of speed or bandwidth where as a kilobyte (noted as K or kb and contains 1024 bytes) is a measure of size or capacity.

Here’s a nice little rant (dated but still relevant) from a post at Stanford