N is for NPC

NPC stands for Non-Player Character. It represents any character that is not controlled directly by a player, usually falling under DM control by default. The character is not defined by any other qualities, so they may be allies or antagonists. In essence, if the players are the main cast, NPCs are the supporting cast.

I like to make my NPCs independent units from the players. They are not the supporting cast in their own story, they're the star! In essence any individual is always the main protagonist in their own story. Just because a ragtag group of ruffians with swords shows up, doesn't mean they get to have their way about town. If the players act out of the social and legal norms, they can expect a visit from the city guards. Adventurers frequently are the bane of polite company and civilization. NPCs do not exist to cater to the party, eagerly waiting for them to arrive so they can magically come to life. They have their own lives and desires.

A Dungeon Master can make an NPC interesting with different voices, but for those not gifted with the vocal talents of Robin Williams, they can give their characters unique physical or personality traits. For the liberal DM, characters can be homosexual or transgendered, to add some flavor. It can be an easy trap to make every tavern owner a gruff grizzled man of forty, and every wizard an old man with a beard. I find it important to try and break from these conventions to allow for more interesting characters and thus a more interesting campaign. Don't think that NPCs must be character races or even sentient, a dragon or a dog can be an interesting character. I've had a lesbian drow slave master, an alcoholic archmage, a blackguard with a penchant for long winded speeches, a necromancer who was a triplet, an ogre tavern owner, and a gay cockney thieves guild master. Characters are as interesting as their personalities, not as their voices, and a good DM will attempt to bring something new from each NPC they create.

Of course, other characters such as henchmen, followers, familiars, or animal companions can be NPCs as well. In the case of those, oftentimes the player will be instrumental in offering feedback on what their personality will be like. A DM can decide on his own how much control he wants over those characters, I myself keep it to a minimum, as I already have so much to do, controlling NPCs that are around the party at all times can be a lot of work.

If you're looking for ideas, Paizo has a number of books and chapters devoted to just NPCs, including the NPC Codex, the NPC Guide, the Rival Guide, and the NPC Gallery within the GameMastery Guide. I would highly recommend any of those books for inspiration for your own NPCs, or even making them up using a great program called Hero Lab, which will help reduce the amount of time you spend making characters from scratch. Thanks for reading, and stay tuned tomorrow for "O is for Ooze".

Relevant Links
D&D 3.5 NPCs
Pathfinder NPCs
d20 NPC Wiki
Hero Lab