Old books are expensive to buy, because they are rare, or because they are hard to find, or because their value will be higher than the original price, so they are precious.

Books are an important part of recording the civilization of human society. Choosing the category of ancient books is very important, and hobbies are the key. Only the subjects you like will be deeply studied and appreciated, such as the red theme, the cultural revolution theme, the rare books of ancient books in the Republic of China and so on.