When we first started working on XDI at OASIS in 2004, the goal was a standard format and protocol for data sharing. We were thinking mostly about the data that was already in databases and other conventional data sources. But now that “everything is turning into data”, the problem space to which XDI applies keeps growing wider.

My latest favorite example is the Book as API post from Alistair Croll’s Solve for Interesting blog. It’s about a talk he and Hugh McGuire gave at O’Reilly’s Tools Of Change conference about the future of the book. It describes how havng an API can unlock the value of the intellectual energy in every book the same way a user interface unlocks the power of a software program.

Read it and you will never look at a book the same way again.

In my case, reading this post through my XDI lens, I saw something even deeper: the future format of books. It starts with the point Hugh makes on slide 97 of his and Alistair’s 100 slide presentation:

Books are made of stuff that can be named.

Hugh then goes on to say in slide 98:

If you name your stuff in HTML (while indexing!), then we can (easily) build new uses/interfaces for our books…

Of course he’s right. The “indexing” Hugh refers to is semantic HTML as explained earlier in his presentation (slides 59-73). But if you “name your stuff” in XDI, then it’s not just semantically understandable, the book and all its contents are globally addressable and composable and semantically reusable (subject to the relevant XDI link contracts) anywhere else it can provide value.

Alistair ends his post:

The killer feature of the book [of the future] is it’s API.

I would go a step further: the killer feature of the book of the future is that it’s an XDI graph.