Squid Game is back and as expected, there’s shocking drama to take in. Every episode will leave you with questions and it’s almost too easy to watch all seven episodes in one sitting. One thing you might have forgotten from season one is why the Squid Game guards all have different shapes on their masks.

Some are circles, some are triangles and others are squares. And the shapes the guards wear all mean different things. Here’s a rundown of the staff hierarchy in Squid Game, and what all of the symbols on their heads mean about their position within the game.

So, here’s what the different shapes on the masks the Squid Game guards wear mean:

via Netflix

Circle: A staff member wearing a circle on their mask is just a straight forward worker, at the bottom of the hierarchy. The majority of the workers are circles. They clean up after the games, set the events up, and take bodies to the incinerator.

Triangle: A triangle on the mask means this person is a soldier – and they are the ones who are armed. They are in charge of enforcing the rules, and “eliminating” contestants.

Square: Anyone who is wearing a square is a manager. Out of the three shapes, the squares have the most power. They oversee the soldiers and workers. Those wearing squares on their masks are able to directly communicate with The Frontman. They also have access to the surveillance room, in which they watch over the players.

The symbols actually have a further meaning. They are the letters of the Korean alphabet, written in Hangul, the Korean writing system. The circle is the letter “O”, the triangle is part of the letter “J”, and the square is the “M”. Together this is OJM, which is the initials of the squid game in Korean – Ojingeo Geim.