Not safe for work (NSFW) is Internet slang or shorthand used to mark links to content, videos, or website pages the viewer may not wish to be seen viewing in a public, formal, or controlled environment.
The marked content may contain graphic violence, pornography, profanity, nudity, slurs, or other potentially disturbing subject matter.
[1][2] NSFW has particular relevance for people trying to make personal use of the Internet at workplaces or schools that have policies prohibiting access to sexual and graphic subject matter.
[5] The similar expression not safe for life (NSFL) is also used,[6][7][8] referring to content which is so nauseating or disturbing that it might be emotionally scarring to view.
[9] Some websites, such as Reddit and OnlyFans, give users the option to designate their content as NSFW in order to warn others of its inappropriate nature.