OpenELEC

Overall Opinion: Open source operating systems have continued to grow as a popular alternative to the "big three" (which of course are Microsoft Windows, Mac OS X and Linux), whether for privacy concerns, hardware requirements or simply to streamline a machine for a certain task. OpenELEC falls into the last category, as it's an operating system specifically used for Kodi media capabilities (Kodi is also open source software). Billed as a JeOS, or "just enough" operating system, OpenELEC is minimal and designed to do a certain thing without bogging down the system with unneeded features. Among its capabilities are a media player and organizer, a photo browser, a television recorder, a personal video recorder, management of TV shows, an audiobook player and a music player.

Pros: Open source code Completely free to download and install, though donations can be made via PayPal or Flattr Uses a very small amount of system resources for operation, making it the obvious choice for machines that are going to be used for nothing but media Since it uses less resources, it's great for smaller machines that have smaller power supplies and graphics cards. It's also ideal for quiet machines that won't need fans since the hardware wont be working hard enough to generate large amounts of heat Furthering its performance on smaller machines is the operating system's ability to offload video processing from the processor to other hardware, such as the graphics card or other decoders Boots incredibly fast, often between 5 and 20 seconds

Cons: Lacks features outside of media playing, making it a poor choice for a typical home or office desktop operating system