Superman & Batman: Generations is the umbrella title of three Elseworlds comic book limited series published by DC Comics in the United States, written and illustrated by John Byrne. A major concept of the series is the avoidance of so-called comic book time; it places Superman, Batman, and the other members of the DC Universe in a single timeline, showing the characters aging and being replaced by their progeny.
Superman & Batman: Generations was published as a four-issue limited series in prestige format from January to April 1999.
Superman & Batman: Generations 2, like its predecessor, is a 4-issue prestige format limited series that ran from October 2001 to January 2002; it dealt with other DC heroes in chapters set between the times of the stories in the first series.
Superman & Batman: Generations 3 is a twelve part limited series. Unlike the previous two series, it was published in standard format, and ran from March 2003 to February 2004.