A subgroup of a group can also be defined as another abstract group along with an injective homomorphism (or embedding) from that abstract group to the given group. Here, the other abstract group can be naturally identified via its image under the homomorphism, which is the subgroup in a more literal sense.
For the skate brand of the same name, see Roller Derby (brand). Roller derby is a contact sport played by two teams of five members roller skating in the same direction around a track. Game play consists of a series of short match ups (jams) in which both teams designate a jammer who scores points by lapping members of the opposing team.
What is roller derby? This is the real deal. None of the action youâll see is scripted or pre-planned; this is a real sport, and we play for keeps. The best way to learn about roller derby is to watch roller derby. Come to a bout or two, and youâll get it. There are fans galore that are willing to explain the rules, talk strategy, and otherwise bask in the glow that is our sport.