Datenschlag is a German-language BDSM support and information site based on a private mailing list and a public website. Datenschlag was founded in 1996 to collect and provide as much information about sadomasochism as possible — as an offspring of that effort, it has compiled the world’s largest bibliography, one of the most extensive history and a dictionary of German BDSM terms.

Datenschlag is furthermore devoted to countering the discriminatory image of sadomasochism in parts of science and the media and to establishing an international network of BDSM information sites.

“Daten” means data, while “schlag” means “to hit” as in “to spank”, but also “to look up (a book)”.