How the software company manages different version of Programs?

Question

Most of the software company have old software which continue maintain, and they also develop current / new software. How they manage different versions of program? Is there any tools to help developers maintain software version? thz

Answer 1

We use subversion with branching/tagging.

Answer 2

In general, people use what is called software configuration management software, which usually includes a version control system like Subversion, Mercurial, git, Visual SourceSafe, et cetera and a project management suite such as Trac, Bugzilla, Google Code, SourceForge and the like. There are about a million options here.

Personally, I'm a big fan of the Mercurial and Trac combination, but lots of people live by Subversion (and people love git, too).

Answer 3

The use a tool called "version control system" or VCS. It allows to keep a history of all changes, give certain points in time a name (like "release 1.0") and to create branches (one for maintenance and one for the next version).

Today, you should have a look at Mercurial or Git. For an introduction to Mercurial, see hginit.com.

All other tools are very expensive (either in terms of your time or your money or both).