The 4, 5, and 6 "Man" Bands of Gaming

Most table top groups tend to be about 4-6 players. There are some indie games that are aimed for 2-5 players, but in general most games I've seen are aimed for 4-6 people. This coincides with the general idea that a 6 player table (not counting the GM) is a "full" table, while a 7 player table is "oversized."

In those games an "optimized" group tends to have certain roles covered. This was a common practice for so long that a lot of experienced players will default to trying to "fill roles" around this when it comes to making characters - and in some cases will complain about their being gaps if people make their characters without knowing what everyone else is making.

Newer games, even mainstream games like D&D 5e, have tried to break this but it is very heavily baked into the lore as much as the mechanics. Even fantasy, sci-fi, anime, and comics will play into these roles when there is a team more than a solo or duo book. So what are they?