Premier League matches will feature Video Assistant Referees (VAR) for the first time and Premier League Champion Alan Shearer has provided simple video guides to help fans understand how the system will work when it makes its debut in Liverpool v Norwich City on Friday.
All 380 matches will be overseen by a VAR, a qualified referee, via screens at the VAR Hub at Stockley Park in west London.
In a series of videos on the Premier League's VAR section, Shearer explains how the VAR will monitor the matches but will be used only for "clear and obvious errors" or "serious missed incidents" in four match-changing situations:
The VAR section also explains how assistant referees will not flag for tight offside decisions, how fans in stadiums will learn when VAR is happening and answers your questions on the system.