Here's a clear breakdown of the basic badminton rules, following official regulations set by the Badminton World Federation (BWF):

1. Objective

Score points by hitting the shuttlecock over the net and into the opponent's court such that they cannot return it.

2. Scoring System

• Games are played to 21 points (win by at least 2).
• Rally scoring: A point is scored on every serve, regardless of who served.
• At 20–20, the game continues until one side gains a 2-point lead.
• At 29–29, the next point (30) wins.

3. Match Format

• A match is best 2 out of 3 games.
• Players switch sides after each game and in the third game when a player/team reaches 11 points.

4. Serving Rules

• Serve must be underhand (below the server's waist).
• Feet must be stationary and within the service box.
• In singles, serve to the diagonal service court based on score:
  • Even score: serve from right side.
  • Odd score: serve from left side.
• In doubles, partners alternate serving/receiving and must follow specific rotation rules.

5. Faults (Loss of Point)

• Shuttle lands outside the court lines.
• Shuttle fails to go over the net.
• Player touches the net with body or racket.
• Double hit or catch on the racket.
• Obstructing or distracting the opponent.
• Serving faults (e.g., illegal serve or wrong service court).

6. Let (Replay Point)

• Shuttle gets caught in the net after serving.
• Both players fault at the same time.
• Disruption not caused by a player's fault (e.g., external interference).

7. Court Dimensions

• Singles court: Narrower (17 ft wide).
• Doubles court: Wider (20 ft wide).
• Net height: 5 feet at the center.