Backporting is the action of taking a certain software modification (patch) and applying it to an older version of the software than it was initially created for. It is part of the maintenance step in a software development process.
The simplest and probably most common situation of backporting is a fixed security hole in a younger version of a piece of software. Consider this simplified example:
- Software v2.0 had a security vulnerability that is fixed by changing the text ‘is_insecure’ to ‘is_secure’.
- The same security hole exists in Software v1.0, from which the codebase for the newer version is derived, but there the text is called ‘is_notsecure’.
By taking the modification that fixes Software v2.0 and changing it so that it applies to Software v1.0, one has effectively backported the fix.
You are running Debian stable, because you prefer the stable Debian tree. It runs great, there is just one problem: the software is a little bit outdated compared to other distributions. That is where backports come in.
Backports are recompiled packages from testing (mostly) and unstable (in a few cases only, e.g. security updates), so they will run without new libraries (wherever it is possible) on a stable Debian distribution. I recommend you to pick out single backports which fits your needs, and not to use all backports available here (the Debian backports repository).