A feature is a useful attribute of something, like a comfort from a technology. Features of often enabled by a function. Programming development often aims to provide a set of features, usually by design. Features are often contained within a specification which suit the intended users preferences.
Programs have lots of features that can be accessed with various interfaces features like a GUI, menu, cursor or a command line. Software is often upgraded to include new and improved features or if something becomes so old it is obsolete.
Interactive multimedia has a growing list of features. Some of the countless features available from the internet is to be able to send huge amounts of email, spy on people with backdoor trojans, stream audio and video, sniff packets or search with a search engine. Features are often something that appear on a variety of other things eg. a power conservation, watermark or skin.