What does build number mean?

[jmsait19]

I notice that many times people ask what the final build of certain releases are. What does the build number mean and what significance does it have to the user?

[janey]

version number, simply put.
the same sense as something like 10.3.5, but build numbers specify specific builds (more in detail), because you can have numerous builds for one minor version.

[Fender2112]

The process of compiling and packaging an application is sometimes referred to as "building". A version such as 10.3.5 will be compiled many times before it is released. Each of these "builds" are numbered so developers can keep track of changes and problems. Think of it as versions of the released version.