First, Linux (sometimes referred to as GNU/Linux or a Linux–based GNU system) is a UNIX–like operating system. Linux is distributed under the terms of the GNU General Public License (GPL) as published by the Free Software Foundation (FSF). Accounts provided by Pictor Design utilize Red Hat Enterprise Linux (RHEL), a widely implemented corporate Linux standard. RHEL is based on open standards and is derived from the community–supported open source project called Fedora. The project is sponsored by Red Hat.
Then, a Virtual Private Server (VPS) is a hosting environment that gives you your own Linux virtual machine. Each VPS accounts provides a protected area that operates as an independent server. It enables you (and multiple customers) to share the expense of hardware and network connections and to eliminate the difficulty of maintaining them. Although multiple VPS customers share hardware, they do not share software. It has its own, complete directory structure, and set of dedicated application software. You can restart it without affecting any other VPS accounts which share the same hardware.