Linux Containers, or LXC, is a type of virtualization in process level. It uses cgroup feature of Linux to work. This way, it creates namespaces to create isolated environment for its process. More details can be found here.
This is a lightweight model of virtualization, because it isn’t a full virtual machine. The same kernel that runs on the host, serves directly the isolated process. Using containers have security impact, once the process encapsulated doesn’t see processes outside of container, and several times you run just needed services in it.
As I said before, the magic happens using cgroup kernel feature, so it must be enabled. The lxc userspace tool must be installed as well. Some templates comes with lxc tool, for debian, fedora, ubuntu… but I never tested it. I have tested on my Slackware64 14.0, following this template. Worth reading.