List of paintball markers
The following is a list of notable paintball markers that have been, or are currently manufactured - ordered by manufacture in alphabetical order. Hopper-fed markers

Pump & Stock Class markers

Pump markers are manually actuated between shots. Stock class markers substitute constant-air for a 12-gram powerlet and hopper for a feed tube. Magazine-fed markers

Magazine designs include the RAP4/Tacamo (more-or-less interchangeable), Dye DAM mag and Kingman mag. Pistols

Pistols are designed to be fired one-handed. They are almost always magazine-fed and powered by 12-gram CO2 cartridges, though hopper and constant-air adapters may be available. Human-powered

.50 cal is common among low-cost mass-produced designs, as the projectiles only require ~1/3 as much energy to fire, compared to .68 cal. References

References
 An attempt of an almost complete listing of all paintball markers ever appeared on the market (German)

Paintball markers