Roller derby gameplay

Each team has five players on the floor at a time, with three different positions: three blockers, a pivot, and a jammer.
The blockers are supposed to create space for the jammer to pass through.
Pivots act as a lead blocker, setting the pace for their teammates and keeping an eye on all that’s happening on the track.
The jammer, meanwhile, is the player who scores the points.
Each team’s jammer starts behind the pivots and blockers (who form the “pack,” the largest group of skaters featuring members of both teams).
The jammer must then try to navigate the pack, going through once without earning points, and then earning a point for each opponent passed after the initial pass-through.
Passing the pack and then getting past the opposing jammer again results in a “grand slam,” which, to the chagrin of baseball purists, results in five points in roller derby.
Each play, called a “jam” is completed after either two minutes of when the lead jammer signals play dead by placing her hands on her hips.
Meanwhile, each “bout” lasts for 60 minutes, with a 15-minute halftime in the middle.
The sport does have penalties that can land players in the penalty box.
One player cannot block to certain areas of another player’s body, including the back or the head, and cannot use their elbows, forearms, hands or head to block. Low blocking, such as intentionally tripping or falling in front of another skater, is also banned.
Other blocking penalties including multiple player blocking (i.e. when two teammates link together in an attempt to block) and out-of-bounds blocking.
There are non-contact penalties such as skating out of bounds and cutting the track, as well as misconduct penalties.