Each team, typically with a roster of 15, fields five skaters during each jam: one jammer, designated with a star on their helmet, and four blockers.

Because roller derby uses a penalty box, power jams, in which one team has a temporary numerical advantage after a foul, can have a major effect on scoring.

Professional roller derby quickly became popular; in 1940, more than 5 million spectators watched in about 50 American cities.

In the ensuing decades, however, it predominantly became a form of sports entertainment, where theatrical elements overshadowed athleticism.

[5] Although roller derby retains some sports entertainment qualities such as player pseudonyms and colorful uniforms, it has abandoned scripted bouts with predetermined winners.

Most modern leagues (and their back-office volunteers) share a strong "do-it-yourself" ethic[10] that combines athleticism with the styles of punk and camp.

[13] Contemporary roller derby has a basic set of rules, with variations reflecting the interests of a governing body's member leagues.

If the jammer passes the entire pack, it is a four-point scoring trip, commonly called a "grand slam".

The pack is the largest single group of blockers containing members of both teams skating in proximity, arranged such that each player is within 10 feet of the next.

[1]: 11  Blockers must maintain the pack, but can skate freely within 20 feet behind and ahead of it, an area known as the "engagement zone".

Blocking with hands, elbows, head, and feet is prohibited, as is contact above the shoulders, below mid-thigh, or to the back.

All current sets of roller derby rules explicitly forbid inline skates for players.

[22][23] Strategies (high-level plans toward achieving the game's goal, which is to outscore the opposition) include the following: Tactics (deliberate conceptual tasks in support of the strategy) may include the following: WFTDA bouts are officiated by three to seven skating referees and many non-skating officials (NSOs).

The growing popularity of roller skating in the United States led to the formation of organized multi-day endurance races for cash prizes as early as the mid-1880s.

[32][33][34] Speed and endurance races continued to be held on both flat and banked tracks in the century's first three decades[35] and spectators enjoyed the spills and falls of the skaters.

[42][43] In the late 1930s, sportswriter Damon Runyon persuaded Seltzer to change the Roller Derby rules to increase skater contact.

[47] For the 1949–1950 season, Seltzer formed the National Roller Derby League (NRDL), comprising six teams.

Jerry Seltzer (Leo's son), the Roller Derby "commissioner", hoped to use television to expand the live spectator base.

Roller derby began its modern revival in Austin, Texas in the early 2000s as an all-female, woman-organized amateur sport.

There are over 2,000 amateur leagues worldwide[52] in countries including Canada, Australia, New Zealand, the United Kingdom, France,[53] Brazil, Germany, Belgium, Finland, Norway,[54] Sweden,[55] Denmark,[56] Israel,[57] Singapore,[58][59][60] UAE,[61][62] Egypt,[63][64][65] Thailand,[66] and China.

[68] Roller derby's contemporary resurgence has been regarded as an aspect of globalization which demonstrates "the speed with which pop culture is now transported by highly mobile expatriates and social media, while also highlighting the changing role of women in many societies".

[2] Many roller derby leagues are amateur, self-organized and all-female[69] and were formed in a do-it-yourself spirit by relatively new enthusiasts.

[76] Each league typically features local teams in public bouts that are popular with a diverse fan base.

[81] Furthermore, corporate advertising has used roller derby themes in television commercials for insurance,[82] a breakfast cereal,[83] and an over-the-counter analgesic.

These typically use word play with satirical, mock-violent or sexual puns, alliteration, and allusions to pop culture.

[89] Copying of derby names has attracted legal and sociological analysis as an example of indigenous development of property rights.

[85][90] The names of roller derby events are also as sardonic and convoluted—for example, Night of the Rolling Dead (Night of the Living Dead), Knocktoberfest (Oktoberfest), Spanksgiving (Thanksgiving), Seasons Beatings (Seasons Greetings), Grandma Got Run Over By a Rollergirl ("Grandma Got Run Over by a Reindeer"), Cinco de May-hem (Cinco de Mayo), and War of the Wheels (War of the Worlds).

[119] As of 2019, the WFTDA postseason includes two playoffs that feed into the Championship tournament, plus three standalone, regionally-based Continental Cups.

Zaina Arafat said in the Virginia Quarterly Review that roller derby defies heteronormativity and patriarchal standards.

Giesler said that female sports objectifies them for the male gaze, but roller derby turns this on its head by disregarding gender roles and norms.