Short answers, pulled from the story.
The bass drum is a large cylindrical percussion instrument with heads at both ends that produces a low note of definite or indefinite pitch. Three major types exist: the orchestral or concert bass drum (also called the gran cassa), the kick drum used in a drum kit and struck with a foot pedal, and the pitched marching bass drum used in marching bands and drum corps, typically played in sets of three to six drums.
William F. Ludwig made the bass drum pedal workable in 1909, paving the way for the modern drum kit. The Sonor drum company had introduced its first single bass drum pedal earlier, in 1900.
The earliest known predecessor to the bass drum was the Turkish davul, a cylindrical two-headed drum used extensively by the Ottoman Janissaries in the 18th century. Its deep sound was valued in warfare for keeping soldiers marching in step. The davul spread across Africa and Europe, eventually evolving through the long drum and the gong drum into the modern orchestral bass drum.
Double bass drumming was first introduced by jazz drummer Louie Bellson, who conceived the idea while still in high school, with Ray McKinley using the setup by 1941. It was popularized in the 1960s by rock drummers including Ginger Baker of Cream, Keith Moon of The Who, Mitch Mitchell of the Jimi Hendrix Experience, and Nick Mason of Pink Floyd.
A marching bass line is a set of graduated bass drums, each tuned to a different pitch, allowing the group to perform melodic and rhythmic passages together. Most high school drumlines use three to five drums, while corps can use up to seven. Each drummer carries one drum and faces perpendicular to the rest of the band, because the drumheads are mounted sideways facing horizontally toward the audience.
Three primary single-stroke techniques exist: heel-down, heel-up, and the floating stroke. For double strokes with one foot, drummers use the slide, swivel, or heel-toe technique. The heel-toe technique, in which the ball of the foot strikes first and the toes follow in a snapping motion, is commonly used in death metal and other extreme genres where speeds of 250 or more beats per minute are required.