Alltagsgeschichte is a form of microhistory that was particularly prevalent amongst German historians during the 1980s. It was founded by historians Alf Luedtke (Wikipedia page , with more information on the French and German pages) and Hans Medick (German Wikipedia page  and French ).
The name comes from German, where Alltag means "everyday life"; it can thus be roughly translated as "everyday history".
In this sense, Alltagsgeschichte can be considered part of the wider Marxian historical school of 'history from below'.
More information on the Wikipedia page