XPointer

In programming, a pointer is simply a location that contains a memory address. Generally, the pointer will contain the address of the first byte of a block of memory. Pointers are also often paired with an offset, which moves you a certain number of bytes away from the pointer in that block of memory. This basic organization is demonstrated in Figure 23.1.

The pointer is used to go to address number 1000, and then the offset is used to move from there to the actual location that's being accessed.

You can create an analogy to this if you're using objects defined in XML files. Consider an instance of <Book> in your catalog database. You could use any unique identifier to go to the specific instance of <Book> and then follow the <Author> ...

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