The standings on the right of every page show each group at a glance. "Pts" is points, "P" is matches played and "GD" is goal difference, the first tie-breaker when two teams are level on points.
Teams are ranked by points first. If teams finish tied, the order is decided by goal difference, then goals scored, and then the head-to-head result between the tied sides. The top two of each group are highlighted because they advance directly to the knockout stage.
Keep an eye on goal difference in the final round of group games — it often decides who survives and who goes home.