>>90257965>Class-based ShooterUsually more players on a team than available classes. Each class has its own unique arsenal, so more customization options.
>Hero ShooterMore heroes to choose from than players on a team. Typically, each hero is usually a combination of different classes where they can make you become a sniper even as a medic, all thanks to their abilities. Also, they often have a rule that disables duplicate heroes on the same team (which is prevalent in competitive and esports scenes).
TF2 is actually somewhere in the middle between the two.