It’s a good idea to tame a group (read: army) of dogs to hunt with. They are great in combat and can help turn the tide in your favor. However, you may want to give them all different names and differentiate them further.
You can easily do that by changing the color of their collar. Simply get a dye for the color you want and right click on the dog. That’s it. You now have a customized dog collar in Minecraft.