Formed in Fort Worth, Texas, On July 4, 1992, Reaper Miniatures is one of the biggest and most recognizable brands in pewter miniatures in North America. The company's mascot is Sophie the (kid-friendly) succubus, with their Bones line having its own pair of mascots in the form of Mr. Bones and Mrs. Bones (the latter even got her own iPhone game). Each year Sophie gets a new promotional miniature, and the Bones family get minis in the Kickstarter projects. Reaper has produced work from numerous sculptors and credits them on their store pages; the female models by Werner Klocke even have their own tag: Klockenbooty.
Reaper produces primarily fantasy miniatures in their Dark Heaven Legends line, while they produce their own wargame called Warlord; the miniatures in that line are also suitable for other fantasy games. Chronoscope is their line for general modern, weird, and speculative fiction miniatures. They also have the official license for Pathfinder, Savage Worlds, and Numenera miniatures.
In response to Wizards of the Coast's Dungeons & Dragons Miniatures Game, Reaper produced the Legendary Encounters line of prepainted plastic miniatures in clear blister packs instead of the blind-packed boxes of D&DMG. After the success of Bones, Legendary Encounters appears to be discontinued as well as the P65 Heavy Metal experiment of cheaper lead casts of their regular DHL line.
Reaper also produces a line of paint, the Reaper Master Series. The MSP line is largely built around triads of shadow, base, and highlight. It has plenty of equivalency with Citadel paints, are cheaper, and come in half-ounce dropper bottles. They have a tool on their website called the Power Palette that lets you pick an area of color in an image and get a mapping to the closest available paint. It's MSP-only of course, but it's useful even if you don't like Reaper paints because of the MSP line's high equivalency with other companies' paints.
Bones is Reaper's line of polymer plastic miniatures (the material is nicknamed "Bonesium" by the community and is just as resilient as the D&D minis are). Bonesium holds paint very well and so the models don't need to be primed before painting, though you may want to undercoat anyway since the material is bright white (with the exception of creatures like elementals, ghosts, and slimes, which are translucent). It has had five very successful Kickstarter campaigns to start and further expand the line, and consists mostly of models from their other lines in the new material, although there are Bones-exclusive models (typically large models that would be a nightmare to manage in pewter). The downside is that Bonesium isn't as rigid as pewter, so characters with weapons tend to find them a bit flaccid when they come out of the pack.
Licensed Doom monster minis produced to promote Final Doom in 1997.