Plex refers to a centralized media playback system which has a server called the Plex Media Server. This server can stream the media to Plex player apps and is available on various platforms, including OS X, Windows, Linux, and NAS devices (e.g., Synology and ReadyNAS). Users can watch shows and view their media library with the use of Apps, which are available for smartphones, PCs, tablets, and even Smart TVs.

Through Plex, the media of the user will be presented in a player app, including the ratings, poster of the show, synopsis, and other information. Additionally, this system also helps the user to keep track of the shows that he has watched and enables him to resume from where he left off. Plex makes this possible by adding the On Deck feature which is available in all Plex Apps and displays the recently added media, the shows that the user is currently watching, as well as the episodes that the user has not yet watched.

The Plex system allows the user to manage his media easily with the use of the Plex Web App, which is a browser-based application. Through the Plex Web App, alterations to the details about a particular show can be made and these changes will be synchronized to all the Plex Apps of the user.

Another useful feature of Plex is that the server can support multiple users and allow them to keep track of what each of them have watched. Each user has his own list of the shows or movies that he has watched and enables him to resume the unfinished ones. However, a Plex Pass is required in order to experience this multi-user support.

Lastly, Plex also converts the HD media into another version, which is more appropriate for the type of device of the user. Through this feature, much less mobile data will be used and the user will find it easier to playback the media in his device.