In the simplest terms, Playerbots allows you to log in multiple characters from a single account (or across accounts) and control them as a party. This isn't like the old "Guardian" pets or the mindless NPC followers you see in Retail WoW. These are fully functional characters.
Well, not literally. But as his level 60 Warrior stood on the same crumbling battlement for the hundredth time, waiting for the Felstriker dagger to drop, he felt every one of those years in his clicking wrist. The official servers had long since bled him dry. Now, he ran a small, quiet AzerothCore server from a repurposed NAS in his garage. Just him, the old world, and the silence. playerbot azerothcore new