Classifying Games
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Axes of game classification.
A structural taxonomy of sporting contests
1. Basic unit of competition
| Type | Description | Examples |
|---|---|---|
| Individual performance | Each competitor produces a separate performance. | Golf, archery, diving, weightlifting |
| Individual head-to-head | Two individuals compete directly. | Tennis singles, boxing, snooker, fencing |
| Team head-to-head | Two teams compete directly. | Football, basketball, rugby, cricket |
| Multiple simultaneous competitors | Several competitors compete at the same time. | Running, cycling, motor racing, swimming |
| Multiple sequential competitors | Competitors perform separately, usually in a prescribed order. | Ski jumping, gymnastics, darts qualifying |
| Relay | Team members perform successive individual stages. | Athletics relay, swimming relay |
| Free-for-all elimination | Several competitors interact, with only one eventual winner. | Some wrestling formats, battle-royale esports |
2. Termination rule
2.1 Fixed-time contests
The contest ends when a predetermined amount of playing time expires. The higher score normally wins.
| Structure | Examples |
|---|---|
| Single continuous period | Some endurance races |
| Two halves | Association football, rugby |
| Three periods | Ice hockey |
| Four quarters | Basketball, American football |
| Fixed number of ends with timed play inside them | Some curling formats |
| Fixed time plus additional or injury time | Association football |
| Fixed time followed by overtime if tied | Basketball, ice hockey |
Basketball therefore ends after four regulation quarters, not after either side reaches a particular score.
2.2 Fixed-number-of-units contests
The contest ends after a prescribed number of holes, innings, ends, frames, rounds, legs, laps, attempts, or other units.
| Unit | Examples |
|---|---|
| Holes | Golf |
| Innings | Baseball; limited-overs cricket |
| Ends | Curling, bowls |
| Rounds | Boxing, combat sports |
| Laps | Motor racing, track cycling |
| Attempts | Long jump, shot put, weightlifting |
| Arrows or shots | Archery, shooting |
| Frames | Some snooker match formats |
| Boards or deals | Duplicate bridge |
2.3 First-to-target contests
The contest ends when a player or team first reaches a specified achievement.
| Target | Examples |
|---|---|
| Points | Many squash and badminton games |
| Games | A tennis set |
| Sets | A tennis or volleyball match |
| Frames | Many snooker matches |
| Legs or sets | Darts |
| Goals | Sudden-death overtime |
| Captures or objectives | Some board games and esports |
Darts is usually a nested first-to system: a player wins a leg by reducing a starting total exactly to zero, and wins the match by taking the required number of legs or sets.
2.4 Exhaustion contests
Play continues until no legal continuation remains, all resources are exhausted, or a terminal position occurs.
| Terminal event | Examples |
|---|---|
| Checkmate, resignation, or draw | Chess |
| No legal move or no pieces | Draughts variants |
| Deck or tiles exhausted | Many card and tile games |
| Last player remaining | Elimination games |
2.5 Distance- or route-completion contests
The contest ends when competitors complete a prescribed course or distance.
| Structure | Examples |
|---|---|
| First across the finish line | Running, swimming, rowing |
| Lowest elapsed time | Time-trial cycling, rally stages, skiing |
| Fixed route with cumulative time | Tour cycling, stage rallies |
| Last competitor remaining | Elimination races |
2.6 Achievement- or failure-triggered contests
The contest ends when a decisive event occurs.
| Event | Examples |
|---|---|
| Knockout or submission | Boxing, mixed martial arts |
| Fall or pin | Wrestling |
| Successful capture | Some pursuit games |
| Failure after progressively harder tasks | High jump, pole vault |
| Insurmountable mathematical lead | Some match-play formats |
2.7 Hybrid termination
Many sports combine several rules.
| Sport | Hybrid structure |
|---|---|
| Tennis | First to points → games → sets → match |
| Cricket | Innings may end through wickets, declarations, overs, time, or successful run chase |
| Baseball | Fixed innings, extended until a winner emerges |
| Golf match play | Scheduled holes, but the match ends early when the deficit exceeds the holes remaining |
| Boxing | Fixed rounds unless ended early by knockout, stoppage, or disqualification |
| Snooker | First to a prescribed number of frames; each frame ends when conceded or completed |
| Darts | First to legs or sets; each leg ends upon an exact checkout |
3. Scoring mechanism
| Type | Rule | Examples |
|---|---|---|
| Accumulative high score | Points are added; highest total wins. | Basketball, football, rugby |
| Accumulative low score | Quantities are added; lowest total wins. | Stroke-play golf |
| Race ranking | Earliest completion or shortest time wins. | Athletics, swimming, skiing |
| Best performance | Greatest distance, height, or weight wins. | Long jump, high jump, weightlifting |
| Judged score | Officials assess quality or execution. | Diving, gymnastics, figure skating |
| Objective completion | A terminal objective determines the winner. | Chess, combat by knockout |
| Unit count | Winner takes the most sets, frames, holes, ends, or rounds. | Tennis, snooker, match-play golf |
| Differential score | Margin over the opponent matters. | Goal difference within a match or league |
| Points-for-place | Finishing positions generate championship points. | Formula One, cycling competitions |
| Combined score | Several unlike performances are converted into points. | Decathlon, modern pentathlon |
| Deduction score | Competitors begin from a maximum or starting total and subtract. | Darts, some judged sports |
| Territory or resource score | Controlled space or captured resources determine the result. | Go, some strategy games |
4. Degree of opponent interaction
4.1 Independent or indirect competition
Competitors do not materially alter one another’s immediate performance environment. They compete against the same standard, course, clock, or measuring system.
Examples include:
- weightlifting;
- long jump;
- diving;
- individual time trials;
- most stroke-play golf;
- separate-lane swimming.
Psychological pressure and changing conditions may still create dependence, but opponents do not directly manipulate the competitor’s ball, body, or legal choices.
4.3 Alternating direct interaction
Players act sequentially on a shared game state. Each move changes the position inherited by the opponent.
Examples include:
- chess;
- snooker;
- pool;
- curling;
- bowls;
- croquet;
- many card games.
Snooker belongs here: the players alternate, play on the same table, and continually change the disposition of the balls. Their interaction is direct even though they do not act simultaneously.
4.4 Simultaneous non-contact opposition
Both sides act at the same time and directly frustrate one another, but are physically separated or contact is prohibited.
Examples include:
- tennis;
- badminton;
- volleyball;
- table tennis;
- squash, although the court is shared;
- many esports.
4.5 Simultaneous contact opposition
Opponents act simultaneously and bodily contact is integral or permitted.
Examples include:
- rugby;
- American football;
- ice hockey;
- boxing;
- wrestling;
- judo.
5. Control of the playing object or state
| Type | Description | Examples |
|---|---|---|
| Separate private objects | Each competitor controls a separate object. | Golf, darts, bowling |
| Alternating shared object | Players take turns acting on the same object or state. | Chess, snooker, curling |
| Exchanged object | An object passes repeatedly between opponents. | Tennis, volleyball, badminton |
| Contested possession | Opponents struggle for control of one principal object. | Football, basketball, hockey |
| Multiple contested objects | Several relevant objects coexist. | Billiards variants, some field games |
| No object | Performance concerns movement or physical dominance. | Running, swimming, wrestling |
| Vehicle-mediated | The principal controlled object is a vehicle. | Motor racing, sailing, cycling |
6. Tactical family
The standard Teaching Games for Understanding classification recognises four major tactical families: target, net/wall, striking/fielding, and invasion games.
| Family | Central tactical problem | Examples |
|---|---|---|
| Target | Place an object accurately relative to a target or obstacles. | Golf, darts, archery, bowls, curling |
| Net/wall | Send an object so that the opponent cannot return it legally. | Tennis, badminton, squash, volleyball |
| Striking/fielding | Strike into space and score before the fielding side retrieves the object. | Cricket, baseball, softball |
| Invasion or territory | Enter or exploit opposing territory while defending one’s own. | Football, basketball, rugby, hockey |
| Combat | Overcome an opponent physically or technically. | Boxing, fencing, wrestling, judo |
| Race | Complete a route or distance faster than opponents. | Running, swimming, cycling |
| Pursuit or tag | Catch, evade, or eliminate an opponent. | Tag, pursuit cycling |
| Stunt or trick | Complete difficult movements or manoeuvres. | Skateboarding, freestyle skiing |
| Rhythmic or aesthetic | Produce a technically and aesthetically assessed sequence. | Gymnastics, figure skating |
| Strength or distance | Maximise a measurable physical output. | Weightlifting, shot put, long jump |
| Route or expedition | Navigate a route, often with environmental decisions. | Orienteering, sailing, climbing events |
| Construction or positional | Develop and exploit a shared abstract position. | Chess, Go, many board games |
The final eight categories extend beyond the traditional four-family scheme, which has been criticised for omitting many widely practised forms of sport.
7. Temporal organisation of play
| Type | Description | Examples |
|---|---|---|
| Continuous | Action proceeds with few formal interruptions. | Football, distance running |
| Stop–start | The clock or play repeatedly stops and restarts. | American football, basketball |
| Alternating turns | Only one side acts at a time. | Darts, golf, snooker, chess |
| Alternating phases | Teams alternate between distinct roles. | Cricket, baseball |
| Rally based | A sequence continues until an error or winning action. | Tennis, badminton, volleyball |
| Attempt based | Each competitor receives a fixed or conditional number of attempts. | Long jump, diving, weightlifting |
| Simultaneous heat | Competitors perform together in a discrete race. | Swimming, sprinting |
| Asynchronous comparison | Performances may occur at different times. | Time trials, postal chess, some esports |
8. Information structure
| Type | Description | Examples |
|---|---|---|
| Perfect information | The complete relevant state is observable. | Chess, Go, snooker |
| Imperfect information | Some relevant state is hidden. | Poker, bridge |
| Uncertain physical state | The state is visible, but execution and physical outcomes are uncertain. | Golf, darts, football |
| Judged information | Outcome depends partly on officials’ assessments. | Diving, gymnastics, boxing decisions |
| Technologically measured | Sensors or timing systems substantially determine outcomes. | Athletics timing, goal-line technology |
9. Source of uncertainty
| Source | Meaning | Examples |
|---|---|---|
| Execution uncertainty | Players cannot execute intended actions perfectly. | Darts, golf, tennis |
| Strategic uncertainty | Opponents’ choices are unknown. | Football, chess, boxing |
| Chance mechanism | Random devices form part of the rules. | Backgammon, many card games |
| Environmental uncertainty | Weather, surface, wind, or course conditions vary. | Golf, sailing, skiing |
| Judging uncertainty | Subjective assessment affects the result. | Gymnastics, diving |
| Mechanical uncertainty | Equipment behaviour matters. | Motor racing, sailing |
| Mixed uncertainty | Several sources operate together. | Cricket, golf, motorsport |
10. Spatial relationship between opponents
| Type | Examples |
|---|---|
| Separate lanes or areas | Swimming lanes, track sprints, archery stations |
| Separated by a net | Tennis, badminton, volleyball |
| Shared space without routine contact | Squash, basketball under non-contact rules |
| Shared space with contact | Rugby, boxing, ice hockey |
| Alternating use of the same surface | Golf, darts, snooker, bowling |
| Parallel or replicated venues | Gymnastics apparatus, weightlifting platforms |
| Extended natural environment | Sailing, orienteering, road cycling |
11. Symmetry of roles
| Type | Description | Examples |
|---|---|---|
| Symmetric | Both sides have essentially the same actions and objectives. | Tennis, football, chess |
| Alternating asymmetric | Teams alternate between unlike roles. | Cricket, baseball |
| Permanently asymmetric | Participants have distinct roles throughout. | Hare-and-hounds games; some multiplayer games |
| Positionally specialised | Overall objectives are shared, but roles differ strongly. | Goalkeeper and outfield players in football |
| Handicap-adjusted | Rules deliberately compensate for differing abilities. | Golf handicaps, some sailing systems |
12. Outcome structure
| Type | Possible outcomes | Examples |
|---|---|---|
| Win–loss only | A winner must be produced. | Knockout tennis |
| Win–draw–loss | Draws are permitted. | League football, chess |
| Ordinal ranking | All competitors are ranked. | Races, golf tournaments |
| Cardinal performance | Raw measurement is independently meaningful. | Running time, jump distance |
| Qualification threshold | Success means exceeding a standard. | Athletics qualification |
| Elimination | Competitors progressively leave the contest. | Knockout tournaments |
| Accumulated championship | Results over several events determine a champion. | Formula One, league football |
| Multiple simultaneous awards | Different classifications coexist. | Cycling jerseys, motorsport classes |
13. Compact identification chart
A contest can be identified by asking the following questions in order.
| Question | Main alternatives |
|---|---|
| 1. Who competes? | Individual, pair, team, or many competitors |
| 2. Do opponents directly affect one another? | Independent, sequentially interactive, or simultaneously interactive |
| 3. Is there bodily contact? | None, incidental, permitted, or essential |
| 4. Is the principal object shared? | Separate objects, alternating shared object, exchanged object, or contested possession |
| 5. How does play proceed? | Continuous, turn-based, rally-based, attempt-based, or alternating phases |
| 6. What ends the contest? | Time, fixed units, target achievement, route completion, elimination, terminal event, or hybrid |
| 7. How is performance measured? | High score, low score, time, distance, judged quality, captured units, or objective completion |
| 8. What is the tactical family? | Target, net/wall, striking/fielding, invasion, combat, race, aesthetic, strength, or positional |
| 9. What information is available? | Perfect, hidden, uncertain execution, or judged |
| 10. What outcomes are permitted? | Win/loss, draw, complete ranking, threshold, or championship points |
14. Worked classifications
| Sport | Structural classification |
|---|---|
| Football | Team; fixed time; continuous invasion game; simultaneous direct opposition; contested possession; limited contact; accumulative high score; draw possible |
| Basketball | Team; fixed time divided into quarters; stop–start invasion game; simultaneous direct opposition; contested possession; accumulative high score; overtime resolves ties |
| Golf stroke play | Individual; fixed holes; alternating shared environment but separate balls; target game; accumulative low score; ordinal tournament ranking |
| Golf match play | Individual or team; fixed maximum holes; hole-by-hole unit scoring; may end early when one side is mathematically uncatchable |
| Darts | Individual head-to-head; alternating turns; same board but no changed shared state; target game; exact reduction to zero; first to a specified number of legs or sets |
| Snooker | Individual head-to-head; alternating turns; shared and persistently altered table state; target and positional game; points within frames; first to a specified number of frames |
| Tennis | Individual or pairs; rally-based net game; simultaneous non-contact opposition; exchanged ball; nested first-to scoring through points, games, and sets |
| Cricket | Team; alternating asymmetric roles; striking/fielding game; runs and wickets; innings terminate through several possible rules; match may be time- or over-limited |
| Boxing | Individual head-to-head; simultaneous contact combat; fixed rounds with possible early termination; judged round scoring or knockout |
| 100 m sprint | Multiple simultaneous individuals; separate lanes; fixed distance; no direct interaction; lowest elapsed time wins |
| Formula One race | Multiple simultaneous individuals and teams; fixed laps or regulated duration; shared course; direct tactical interference; ordinal finish converted into championship points |
| Diving | Sequential individual performance; fixed attempts; judged aesthetic and technical score; no direct interaction |
| Chess | Individual head-to-head; alternating turns; shared abstract state; perfect information; terminal objective or agreed draw; no fixed score accumulation |