what do you mean by knock out tournament
Single-elimination tournament A single-elimination, knockout, or sudden death tournament is a type of elimination tournament where the loser of each match-up is immediately eliminated from the tournament. Each winner will play another in the next round, until the final match-up, whose winner becomes the tournament champion. Each match-up may be a single match or several, for example two-legged ties in European football or best-of series in American pro sports. Defeated competitors may play no further part after losing, or may participate in "consolation" or "classification" matches against other losers to determine the lower final rankings; for example, a third place playoff between losing semi-finalists. In a shootout poker tournament, there are more than two players competing at each table, and sometimes more than one progressing to the next round. Some competitions are held with a pure single-elimination tournament system. Others have many phases, with the last being a single-elimination final stage, often called playoffs.
Double-elimination tournament As with single-elimination tournaments, most often the number of competitors is equal to a power of two (8, 16, 32, etc.) so that in each round there is an even number of competitors and never any byes. The maximum number of games in a double-elimination tournament is one less than twice the number of teams participating (e.g., 8 teams – 15 games). The minimum number is two less than twice the number of teams (e.g., 8 teams – 14 games).