Before the season a team publishes the list of athletes eligible to compete for it. That list is the roster. It defines who belongs to the squad and in what numbers.

Rosters are shaped by rules on squad size, salary caps, draft systems, and eligibility. Coaches and management choose which skills and roles to prioritize. Injuries, transfers, and form lead to changes during the season. Depth on the roster determines how well a team absorbs absences.

Fans study rosters to assess prospects; opponents study them to prepare tactics. Being on a roster is the first requirement for participation; earning actual playing time is the next challenge. A well-constructed roster balances star quality, experience, youth, and positional cover.

The roster is the raw material from which the team on the field is chosen.