So what you are looking at is a graph telling you the different percentage of battery use across the different processes in the phone.
So in your case after 6 hours 16 minutes and 9 seconds of use you have used 40% of your battery. Then it lists which parts/apps/processes are using which percentage of battery. It helps to know in case something is draining your battery and you need to find out what it is. The percentages listed next to each item give you an idea of how much battery is being used by that specific feature. If you click on screen it will tell you how much time your screen has been on. This helps to know because "screen on time" is usually what uses the most battery.
I don't know if that helped.