Stories of Arn
Whenever you enter a town, you'll be able to find at least one bulletin board with various pieces of news and job listings. These job listings are radiant quests. Usually, these quests will be fairly quick and simple quests, often only requiring a basic skill check and a bit of your time.
There are two types of radiant quests: Help Wanted and Bounty quests.
Help Wanted quests are usually from private citizens. They request aid in some for or another. Usually, they need you to collect some item from outside the safety of the city walls, craft some item, or take an item to another person. Outstanding Help Wanted quests have a small retardation effect on the growth of the town.
Bounty quests are usually from some government organization, often the town guard. They request aid in capturing or killing some fugitive or monster. These are generally slightly more involved than Help Wanted quests, but also reward better in turn. Outstanding Bounty quests have a large retardation effect on the growth of the town unless they are on-going quests, such as bringing an apothecary any herbs you find.
Every week, a town has a chance to get a new radiant quest. For each outstanding quest, the chance is decreased. After a radiant quest has been active for roughly a month, there is an increasing chance for it to be removed each week.
Outstanding radiant quests have a retardation effect on the growth of the town, so completing radiant quests in your favorite town will help it grow faster.