Players and psychology
Reg (regular) in poker
Definition
A regular: an experienced player who plays the same stakes often and usually has a solid, studied game.
Regs know each other's tendencies and play tighter against one another. The edge in reg-versus-reg pots is small, so many winning players avoid tables full of regs and look for weaker opponents.
Stats from a HUD are most reliable on regs because you meet them many times.