Areas of Study 

Sometimes you will be called upon in game to know something about a particular subject. If you have added the right area of study to answer the question, the DM will tell you what you want to know. 

For example, you come across a purple-leafed plant in the forest and don't know if it's safe to eat. If you have either the nature or the potion-making area of study, you can ask the DM and they will tell you what the plant is. (an edible plant that causes mild sleepiness, etc.) 

If you don't have any of the applicable areas of study, you are on your own to see what happens.