The DifferenceA bug is something that can be reasonably viewed as a problem. This can include things that aren't explicitly in the requirements based on norms of an industry or organization. If a contractor installs a door upside down, a reasonable user would see that as a bug.A feature is something that hasn't been requested. In many cases, business units expect that something will be done without documenting it anywhere. This is unfair to teams who work hard to deliver a set of requirements only to find the product doesn't meet unstated expectations that exist in someone's head.
Bugs as FeaturesSoftware development folklore includes many wild stories about bugs that turned out to be valuable features. For example, a video game character that acts crazy due to a bug that becomes a beloved feature of a game. In other variants of the story, developers make wild claims that severe bugs are actually features.
Features as BugsIt is common for users to report unpopular features as bugs. If most of your users believe that a feature is a bug it is moot to argue the point.
|Bug vs Feature
Something that can be reasonably viewed as a problem based on current requirements.
Something that hasn't been requested in current requirements.