[198d]

I don't think it's quite that simple. The index that google serves search query results from is a direct result of the algorithms they've applied to the data the googlebot has gathered. If by 'index' the author means the data the goolebot (for example) has downloaded from the internet, that's quite a bit different, but still probably serves the purpose the author is looking for. The index is a highly specialized representation of all the data they've collected.

[jessriedel]

> If by 'index' the author means the data the goolebot (for example) has downloaded from the internet.

That's what the author means by 'index'.