Roller derby is a sport in which two teams of women, wearing Roller Derby uniforms, helmets, elbow pads and knee pads, skate on roller skates around a track. In Roller Derby there are blockers and jammers, which are used to block or punch through the other teams defense. Each blocker will be assigned a dodging technique that they will use to gain floor space from their opponents without being penalized. Roller Derby can be exciting.