Angie dont worry you will learn it all soon, when i first started i read any book i could find, researched things on the internet, the thing is its fun doing that but dont worry if you dont remember it, i find i usually only learn things if i use it practically or in a certain situation, dont worry if you dont know all of the different styles and things, you will learn soon. The thing is also dont focus too much on the styles, they are supposed to just be a guideline set by the Japanese so that the Western Culture could understand and practise the art of Bonsai properly