Google on Thursday introduced a major change to its core search engine to mark the company's 15-year anniversary. Described as the biggest change to the core algorithm since the launch of Caffeine in early 2010, Hummingbird is said to be the result of a foundational rethink of page ranking and indexing - two core elements that must work in tandem for a search engine to be successful - by tapping into the company's Knowledge Graph.

For the general user, the change should result in more personalized and complex searches but it won't be overly obvious for most. For example, a user looking for a nearby car-rental facility could ask "Where is the closest car-rental place?" instead of simply typing "car rental (zip code)." Google can now also handle comparison questions like "Which is better for me - olive oil or butter?"

The algorithm quietly rolled out about a month ago and is already in place for roughly 90 percent of Google searches worldwide according to senior vice president of search Amit Singhal. Hummingbird is said to read pages differently to try and understand exactly what is being said on each page. This is important as Google strives to understand how content is relevant, what specifically it means and how it relates to other pages.

Unfortunately for us, Google didn't offer much in terms of technical details on exactly how Hummingbird works.

Last but not least, Google will be launching a new version of the Google Search app for iPhone and iPad. With the update, users will get notifications like reminders across devices. What's more, the update will show Google Now notifications. A few more usage scenarios are provided on Google's Search Blog if you wish to dig deeper.