The bounties in are a big part of the game and one of the best ways to get better gear. Not all of them will reward you with better gear alone, but all of them will give you a significant amount of coins for the area you are in, allowing you to buy better versions of your favored weapon or armor.
This can significantly reduce the difficulty of the enemies you face, as the number of skulls next to their names will slowly decrease.
There are some strong enemies in and the bounties will ask you to defeat many of them. Knowing where they are before you head out into the wilds is also a good thing, as it allows you to avoid accidentally walking directly into one before you are ready.
Knowledge is power in this instance, and you will need to have every bit you can muster to face some of these bounties depending on the part of the playthrough you encounter them.
There are 4 regions with bounties in and each of them have 5 bounties. Many of them don't give you extra rewards, but they will all give an amount of XP and gold depending on the region.