If you have used a modern camera you will be aware that one of it’s weakest aspects are digital camera batteries, they can run out ver quickly with only a few photos. Different cameras use different types of batteries.
Some cameras have internal batteries like the iPhone and most Canon cameras. These batteries can be recharged and in the long run will cost less than cameras that use disposable batteries since you can use the same battery over and over. The downside is that if you are on location it is not easy to add extra battery power if you run out.
Other cameras use disposable batteries that can be purchased at any convenience store. These are great if you will not be near a charger and use a lot of batteries. The downside to the cameras is the expense of always replacing the battery. You can save a little money by purchasing rechargeable AA batteries but you may not get as many photos per charge as some other options.