From his Wikipedia page:
Jacob Kurtzberg (August 28, 1917 – February 6, 1994), better known by the pen name Jack Kirby, was an American comic book artist, writer and editor. Growing up poor in New York City, Kurtzberg entered the nascent comics industry in the 1930s. He drew various comic strips under different pseudonyms, ultimately settling on Jack Kirby. In 1941, Kirby and writer Joe Simon created the highly successful superhero character Captain America for Timely Comics. During the 1940s, Kirby would create a number of comics for various publishers, often teamed with Simon.
After serving in World War II, Kirby returned to comics and worked in a variety of genres. He contributed to a number of publishers, including Archie Comics and DC Comics, but ultimately found himself at Timely’s 1950s iteration, Atlas Comics. In the 1960s, Kirby co-created many of Marvel Comics’ major characters including the Fantastic Four, the X-Men, and the Hulk along with writer-editor Stan Lee. Despite the high sales and critical acclaim of the Lee-Kirby titles, Kirby felt treated unfairly, and left the company in 1970 for rival DC Comics.
While working for DC, Kirby created his Fourth World saga, which spanned several comics titles. While these and other titles proved commercially unsuccessful and were canceled, several of their characters and the Fourth World mythos have continued as a significant part of the DC Comics universe. Kirby returned to Marvel briefly in the mid- to late 1970s, then ventured into television animation and independent comics. In his later years, Kirby received great recognition for his career accomplishments, and is regarded by historians and fans as one of the major innovators and most influential creators in the comic-book medium.
In my opinion the comic industry would not be what it is today if it were not for the creativity and imagination of Jack Kirby. While reading his Wiki page you can not help but be overwhelmed by the number of comics and characters he had a hand in creating. Unfortunately for the comic industry there will never be another like him. Jack Kirby would have been 92 today.
If you are to young to know about what Jack Kirby meant to comics please take the time to read and learn more about him.