A background is an image of pixels that together form up to become scenery, like a plain or a forest. Good backgrounds are not essential to making a good comic series ('as seen in Angry Nidhiki's Lol with Angry Nidhiki), but they do help to make them more aesthetically pleasing.
Many early comics, such as most of Mike's Comics and Season 1 of Dark709's Comics used plain white backgrounds (Mike's Comics did feature colored backgrounds, albeit rarely), and relied on humor more than visuals.
Paint is most commonly used by comic makers who aren't equipped with GIMP, Adobe Photoshop or other graphic-creating programs. Though it is much more difficult to make high-quality backgrounds with Paint, the program is able to create relatively satisfying backgrounds with minimal lighting. This is one of the leading reasons for most comic-makers to get a more powerful graphics editor. However, there are some authors, such as Nuvaro in Bionicle Star Wars, who have proved in their series that it is possible to make some good backgrounds in Paint.
GIMP, being one of the most accessible programs, due to being free, is the most widely used program for creating backgrounds. It has been praised by many for its well made backgrounds, though some Photoshop user simply call it "the next big thing." Two of the most notable users of GIMP are Dokuma and Nuparurocks, who began the usage of GIMP in background making and effects. It is also said that Dark709 pioneered the usage of GIMP through his comics.
Photoshop is the least used of the three main programs. The use of Photoshop for backgrounds are believed to have started when Tahuri and Kotahn, both experienced Photoshop users, began using Photoshop backgrounds in their comics. However, the earliest known use of Photoshop for backgrounds (particularly the grass brush) was by Teox. Following Tahuri and Kotahn's use of the program, more came to see how well Photoshop could produce realistic backgrounds. Turaga Dlakii has also used Photoshop in his comics to produce highly detailed backgrounds. Other notable Photoshop users include Metrukuta and Xanis.
Photoshop Elements is a simpler version of Photoshop, adapted mainly for photo editing, that has been used to make backgrounds as well.It is much easier to acquire than the full Photoshop, due to its lower price (1/9th of the cost of Photoshop), and wider availability. It has been used by multiple BZPower members such as Eljay, Arc1110, XFire, and Mr.Maniac.
The Comic Kit
The Comic Kit is a kit created by BZPower member Nuparurocks. It contains multiple backgrounds, accessories, borders, and other assets for new comic makers, or those unexperienced with programs like GIMP and Photoshop. NR first created the kit on a bet with Angry Nid, and figured that a couple of people might use it. Simply put, he was wrong. A lot of people used it, and the backgrounds from the kit became some of the most widely used backgrounds on BZPower.
Since the kit has become such a phenomenon, it has become a sort of cliché, leading many authors, including Nuparurocks himself, consider it annoying.