about that transaction that make it nonintermptible. So, for example, let's say you are transferring $100. You can't interrupt it halfway through and end up with $100 in both places, and you can't lose $100 in the transaction. The transaction either happens all the way or it doesn't happen at all. That is part of what is meant by a transaction in database terminology.
In our case, if the buyer decides he wants to read something, then that reading is like engaging in a transaction. If he wants to lend it to a friend, we will have to go through a process of what it means to lend out a database. Typically, if you lend out a book, while your friend has the book, you can't use it, and then when he returns it to you, you can use it again. There is a period of time during which only one copy is in use. That is different from making a copy, in which case both people can use it at the same time. And, if he wants to reuse some portion of the database—digitally extract some portion of the work—that comes under the category of derivative works.
One of the inventive aspects of creating this kind of technology was to invent a rights language and to understand the different kinds of rights that matter. Depicted in Figure 5.1 are the elements of a typical right whereby, if you bought a digital work, there would be a collection of rights and each right would have the following kinds of elements to it. The first would be a permission category that identifies a right. There are three kinds of so-called transporting rights: copy, transfer, and loan, which should be clear from the previous example. Then, there are rendering rights. These include things like playing—if it is music, you could play it on a loudspeaker or a video; you could play it on a speaker. If it is a computer game, you could play it. Printing is rendering to a medium outside the zone of trust. If you think of the computer as being a trusted system, then printing the work on a piece of paper means that it is no longer being controlled digitally in any way. Exporting means to move a file copy of the work in some form