Article: The governing bodies in each country operate league systems in a domestic season, normally comprising several divisions, in which the teams gain points throughout the season depending on results. Teams are placed into tables, placing them in order according to points accrued. Most commonly, each team plays every other team in its league at home and away in each season, in a round-robin tournament. At the end of a season, the top team is declared the champion. The top few teams may be promoted to a higher division, and one or more of the teams finishing at the bottom are relegated to a lower division.

Now answer this question: What is the name for the type of tournament teams play in regular season?
round-robin