There have been adjustments, changes, and what seems like complete rewrites of the algorithm that Google started with in the beginning. At first when you searched, the results you were given were based directly upon the query as you’d entered it, and sorted by how many back links it had. Now however, when you search for ‘Winnipeg Jets’, images and video for the team appear even though the words “images” or “videos” weren’t in the query.
The algorithm that Google, Bing and a handful of others use, has grown and evolved to a point where it’s trying to anticipate what you’re searching for, as well as the direct query you may have typed. The search engines are getting better at bringing what you want to see on your given topic, and seem to be weighing the number of clicks through to a result as well as all of the previous criteria as well. As you’ve probably mistakenly typed a word or two while searching as well, you’ve probably noticed that search engines are also able to correct spelling mistakes which are commonly made. What the engines are getting much better at doing however, is not correcting your spelling, but interpreting what you may actually be searching for. Google can load dictionaries of how words should be spelled and common misspelled variations of those words and can look at how searchers correct searches and when they click on different variations. And it can use this data to not only suggest a query with a different spelling but to treat the misspelling as a synonym behind the scenes and rank the correctly spelled matches.
And as with what goes in the same basket as interpreting what you might be looking for, Google is noticeably moving forward on trying to discern your intent while searching as well. A basic description of how it works:
Keyphrases don’t have to be in their original form. We do a lot of synonyms work so that we can find good pages that don’t happen to use the same words as the user typed. – Matt Cutts
Even Bing is getting in on the act as if you mispell a common word or phrase, you’ll still often be brough to the correct results. Perhaps soon enough, you won’t need to search by typing, but by simply visiting your preferred search engine. And because you researched a new car and purchased one via online dealership shopping, the engine knows that in a few months it should perhaps deliver you information on local garages which offer oil changes and tire rotation services.