Since 1998 Google has used the same old algorithm and upgrading it iteratively every year. Google recently replaced it's entire algorithm with a new version.
This is equivalent to taking a 1950's model corvette and swapping out the engine with a brand new fuel injected, recently engineered engine capable of much more than any motor from the 50's.
Well in short it's faster and more precise than previous versions of Google.
One of the deepest changes that makes Hummingbird so different than past versions of the Google algorithm is that it now focuses more on conversational search. Google has said that less people are searching seriously with short keyword terms and focusing more on the longer tail keyword searches asking for multiple data points simultaneously.
This means Google is ultimately looking less at what each keyword in your query means and more at what your entire query means.
Sometime around August 20th Google switched out the old way of doing things with the bigger, better and faster Hummingbird algorithm. Google officially announced the new launch on September 26th 2013 although they've been using Hummingbird for about a month.
Come on, not again. Every time Google does anything everyone I know tells me "you know SEO is going away now that Google did yadda yadda, blah blah." Hummingbird doesn't change anything about the way we do SEO. It still works the same, sites are ranked based on several factors both onsite and offsite. Here's what Danny Sullivan of Search Engine Land had to say about it:
No, SEO is not yet again dead. In fact, Google’s saying there’s nothing new or different SEOs or publishers need to worry about. Guidance remains the same, it says: have original, high-quality content. Signals that have been important in the past remain important; Hummingbird just allows Google to process them in new and hopefully better ways.
Again, this is a good change for search and simultaneously what we do in SEO.
Well since Google is paying more attention at what an entire query means, focus more on providing usable information to your visitors. This means:
Ultimately, it's probably not Google that pays you. You just need PEOPLE to find you. There are so many other ways to get eyeballs than through Google so focus on those areas first and Google will be sure to follow.