My book is priced at 2 1.8, which is different. If you have read books at two prices, what is the difference between reading books first, such as paper and cover?

First of all, coated paper is definitely different from ordinary paper. There are many kinds of paper, and the price of each paper is different. Then the cover, some of which are hard covers, should be more expensive than ordinary ones.

There is also the problem of version. I bought this version in June and September. In fact, the content is the same, but some people who want to collect it may buy it, as long as the paper cover of the book is different.