Apt-Pinning
by Anton Piatek
If you run a Debian or Ubuntu system and have more than one release in your apt-sources file (/etc/apt/sources.list) then you should probably learn the basics of apt-pinning. Apt-pinning allows you to have a specific package stay at a certain level or set a preference for it to be installed from a specific release. This way you can have the latest version of package X from a cutting-edge server without worrying about the rest of your packages moving up to cutting-edge levels by accident.
Two excellent resources are:
tags: Debian - Linux - ubuntu