A follower is a creature controlled by the GM, such as an NPC, who is a temporary or permanent member of the adventuring party.
Followers are typically passive during the adventuring and interaction phases, simply going along with the player characters' decisions unless they are directly addressed or told to do something. NPC followers may argue with the party's actions depending on their relationship level to the party.
During combat, followers act on their own turns. They have their own stats, including initiative, and roll initiative separately from the player characters. They act as allies with the party, defending them and attacking enemies using their own abilities.
The GM may choose to temporarily control a player character as a follower if a player is absent from a game session.
Main Page: Companions
A companion is a special type of follower who trusts a single party member completely and exclusively. Like followers, companions have their own stats and act on their own turns. Companions, however, are controlled by the player who has gained that creature's allegiance. That player directly controls their companion during its turn.