Explanation:
A knockout tournament is a form of combination tournament where participants compete in a series of single-elimination rounds until only one winner remains. In a knockout tournament, each participant is paired with another participant, and the loser of each match is eliminated from the tournament. The winner of each match advances to the next round until the final round, where the last two remaining participants compete for the championship.

A knockout tournament is characterized by its single-elimination format, which means that a participant must win every match to progress further in the tournament. Once a participant loses a match, they are immediately eliminated from the competition and cannot continue to compete for the championship.

Key Points:
- Combination Tournament: A knockout tournament is a type of combination tournament where participants compete in a series of matches.
- Single-Elimination Format: In a knockout tournament, a participant is eliminated from the competition after losing a single match.
- Pairings and Advancement: Each participant is paired with another participant, and the winner of each match advances to the next round.
- Final Round: The knockout tournament culminates in a final round where the last two remaining participants compete for the championship.
- Winner: The participant who wins the final match is crowned as the champion of the knockout tournament.

Example:
Let's take an example of a football knockout tournament. In the first round, there are 16 teams competing. Each team is paired with another team, and they play a single match. The winner of each match advances to the next round, while the loser is eliminated. After the first round, there are only 8 teams remaining. The process continues, with each subsequent round halving the number of teams. Eventually, there are only two teams left, and they compete in the final match. The winner of the final match becomes the champion of the knockout tournament.

This format ensures that the tournament progresses quickly, as each match eliminates half of the remaining participants. It also adds excitement and suspense, as one loss can result in elimination from the competition. Overall, a knockout tournament is a popular and thrilling format used in various sports and competitions.