Manual

Settlement Amenities
These are some of the amenities you can find in a settlement. Only the greatest of
cities will have them all, but most have at least an inn and a few merchants.
INNS
Inns are situated in most cities and camps, and provide players a place to rest.
If you log out in an inn, your character will accumulate rest bonus faster so that
the next time you login to play, you'll earn more experience for kills. Inns also
have merchants that will sell you food.
BANKS
Only large cities have banks, where players can store items they do not wish
to carry. Banks across Azeroth are linked so you can access your storage from
any bank in the world by talking to a banker NPC.
MERCHANTS
Larger settlements will have the most merchants, including specific ones
devoted entirely to trade skill ingredients, armor types, and more specialized
items. Smaller settlements might only have a general goods merchant for the
most common items. To find the widest range of items, you will need to
venture to large cities and capitals, but if you need only simple items like food
or drink, you can usually find those at any town.
TRAINERS
The class trainers for all the classes usually can only be found in capitals and
major cities. Even then, capital cities usually will only have trainers for classes
specific to their main population. You won't find paladin trainers in the tauren
city of Thunder Bluff, for example. Trade skill trainers, on the other hand, are
more common, although you still won't find them in remote towns or camps.
FLIGHT MASTERS
Most zones have at least one major settlement with a flight master to connect
the zone to other flight paths in the continent.
There is no hard rule about what each settlement has. You have to explore
them yourself, or ask in the general chat channel, to find out what non-player
characters reside in each settlement.