Batman
The first Batman story, "The Case of the Chemical Syndicate", was published in "Detective Comics" #27 (May 1939). Finger said, "Batman was originally written in the style of the pulps", and this influence was evident with Batman showing little remorse over killing or maiming criminals. Batman proved a hit character, and he received his own solo title in 1940 while continuing to star in "Detective Comics". By that time, Detective Comics was the top-selling and most influential publisher in the industry; Batman and the company's other major hero, Superman, were the cornerstones of the company's success. The two characters were featured side-by-side as the stars of "World's Finest Comics", which was originally titled "World's Best Comics" when it debuted in fall 1940. Creators including Jerry Robinson and Dick Sprang also worked on the strips during this period.
The Batman Chronicles (trade paperback)
The Batman Chronicles is a series of trade paperbacks published by DC Comics, intended to reprint all Batman stories from "Detective Comics", "Batman", "World's Finest Comics", and other titles throughout the character's history, chronologically (based on publication date), starting with his earliest appearances. Whether or not the series will collect the post-Crisis version of Batman as well remains to be seen. They are priced significantly lower than the "Batman Archives" series in order to be more affordable for the reader. Each volume is typically priced at $14.99 USD. 11 volumes have been produced so far. After a 2-year hiatus, "The Batman Chronicles" returned with volume 11 in December 2012. No further volumes have been announced yet.