Do you know exactly what a trillion means? It’s 1 followed by 12 zeros (1, 000, 000, 000, 000). Google states that their system used to find links and new contents had just hit a milestone of finding 1 trillion of unique URLs on the web at once.
So you might be wondering if Google is now indexing more then a trillion web pages then? Well, that doesn’t seems to be the case as Google was fast to point out that:
We don’t index every one of those trillion pages — many of them are similar to each other, or represent auto-generated content similar to the calendar example that isn’t very useful to searchers. But we’re proud to have the most comprehensive index of any search engine, and our goal always has been to index all the world’s data.