Ranks are used in Pixel Gun 3D to keep track of each player's individual performance level.
Ranks are split into different sub-ranks, and players are able to climb up in these ranks by earning skill points in Singleplayer or Multiplayer battles. This means, that the amount of skill points a player has earned, the higher rank he/she will have. Every time you level up, you get a coin bonus. This bonus raises every time you level up. There are currently 26 ranks (as of 9.0.0). It might be possible for more ranks to be available in future updates.
As of 9.0.0, you get coins and 10 gems as you rank up.
Note that after 8.0.0 update, the amount of bonus coins you receive for leveling has dropped dramatically.
Old Ranks Symbols
Tiers
Tiers are an unmentioned system within Pixel Gun. The tiers consist of players levels 1-4 (tier 1) and players levels 5-13 (tier 2). The tiers cannot play with each other in multiplayer.
As of 7.1.0, however, these ranks have been dissolved.