Parallels Plesk Panel is the best choice for hosting providers, web designers and site owners. Parallels Plesk Panel 11 is a version of the program that offers a number of new benefits and features for each type of user.
Parallels Virtuozzo Containers - operating system-level virtualization solution, a product of Parallels, Inc. This implementation allows running multiple isolated copies of the operating system on a single physical server.
CloudLinux introduces the concept of LVE – LightWeight Virtual Environment for user isolation. Each LVE has the severe restrictions on CPU, memory, maximum quantity of processors and disk input-output which can not be exceeded.