Divers offer a better waterproofness than traditional watches. They are equipped with a graduated rotative bezel in order to calculate diving time and they also feature a better luminescence.
The date is a small window on the dial which indicates the day of the month (between 1 and 31).
Watches featuring a small seconds have a smaller subcounter, usually located at 6h, which indicates seconds.
The power reserve indicator tells you the time the watch will continue to function. It can either be seen on hand winding or automatic watches.