What happens when the ball goes into touch in rugby sevens?

• Who throws: the opposition of the player who carried or kicked the ball into touch, in the ordinary case.
• The 50:22: a kick from a player's own half that bounces into touch in the opposition's 22 gives the throw to the kicking team.
• 15 seconds: "Teams form the lineout within 15 seconds of the assistant referee or touch judge indicating the mark of touch." Free-kick.
• How many: "A minimum of two players from each team are required to form a lineout."
• The throwing team decides: it sets the maximum number in the lineout. The other team may have fewer but not more.
• The throw: "straight along the mark of touch", reaching the five-metre line before it hits the ground.
• Not straight: the other team chooses a lineout or a scrum, if it lifted a player to compete. If it did not compete, play continues.
• Lifting: allowed once the ball has left the thrower's hands. The lifted player must be lowered safely.
• Offside: lineout players stay on their own side of the mark until the ball has been thrown and touched a player or the ground.
• Quick throw: the team entitled to throw may throw in before a lineout forms, with the same ball, from between the mark and its own try line.
• A kick-off into touch: not a lineout if it went directly. In sevens that is a free-kick.

The glossary has the lineout, the throw-in, the quick throw, the 50:22, the touchline and the kicked directly into touch entry.

The lineout is a fair contest for a ball that has left the field: thrown down the middle, with both teams able to jump. In sevens it is small and fast, often two or three players. The quick throw matters more, because a team that takes it before the defence arrives has a whole pitch to run into.