A Power User has more knowledge and a deeper understanding of both hardware and software, with at least some ability to change hardware parts and configure software ... possibly an ability to run hardware diagnostics, do hardware repairs, and write and compile software ... while a regular user can only turn a computer on and use what software is already installed.

Power Users from TechTerms.com: http://www.techterms.com/definition/poweruser Power User When it comes to computers, there are regular users and there are power users. Most people fall into the regular computer user category. These types of people use their computers for basic functions like Web browsing, sending e-mails, typing papers, working with spreadsheets, doing finances, and playing games. Regular computer users can typically get by with a middle-of-the-line computer that is fast enough to do their everyday work. Power users, however, require top-of-the-line machines that are optimized for their work purposes. Power users include video-editing professionals, high-end graphic designers, audio producers, and those who use their computers for scientific research. Professional gamers (yes, there is such a thing) also fall under this category. These users seek the latest and greatest systems because no computer is really "fast enough" to suit their needs. Even the fastest computers can take substantial time to render large amounts of video and audio or to manipulate large images. Gamers want machines that will play their games in as many frames per second (FPS) as possible. So, to be a power user means to never be really satisfied with your system, but to always want something faster and better. Then again, that sounds like most of us, but power users usally have justifiable reasons. End User from TechTerms.com: http://www.techterms.com/definition/enduser End User An end user is the person that a software program or hardware device is designed for. The term is based on the idea that the "end goal" of a software or hardware product is to be useful to the consumer. The end user can be contrasted with the developers or programmers of the product. End users are also in a separate group from the installers or administrators of the product. To simplify, the end user is the person who uses the software or hardware after it has been fully developed, marketed, and installed. It is also the person who keeps calling the "IT guy" with questions about why the product isn't working correctly. Generally, the terms "user" and "end user" mean the same thing.