Batman is an ongoing American comic book series featuring the DC Comics superhero Batman as its main protagonist. The character first appeared in Detective Comics #27 (cover dated May 1939). Batman proved to be so popular that a self-titled ongoing comic book series began publication with a cover date of Spring 1940. It was first advertised in early April 1940, one month after the first appearance of his new sidekick, Robin, the Boy Wonder.
Though the Batman comic book was initially launched as a quarterly publication, it later became a bimonthly series through the late 1950s, after which it became a monthly publication and has remained so since. In September 2011, The New 52 rebooted DC's continuity. In this new timeline, the original Batman series ended and was relaunched with a new first issue.
In 2016, DC Comics began a second relaunch of its entire line of titles called DC Rebirth. Batman (vol. 3) #1 (August 2016) was the debut bimonthly relaunch of the comic book series.
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