Google turned 19 on September 27, 2017. But still, there are people who debate over its age as 20. Even Google seems to be confused over its birth date as it celebrated its birthday on four different occasions.

Google is famous for marking every day with a doodle to remember key events, dates and people. But looking at the past trend of Google celebration doodles, it is evident that even its founders debated over the selection of date when Google embarked its journey.

However, there is an explicit mention of Google's incorporation date as September 4, 1998, on its official page. However, the first doodle which marked the celebration of Google's birth came on September 27, 2002, which also happened to be its 4 th birthday.

Later in 2003, the date again got shifted to September 8 and yet again in 2004, Google changed it to September 7. Even the change did not stop here and the subsequent year, i.e. 2005, witnessed the birth date as September 26.

It is important to know how Google came into existence to capture the important milestones. The conceptualisation of the idea around Google started sometime in 1995 when Larry Page and Sergey Brin were PhD students at Stanford University, Sandford, California. The same year was also the beginning of a long-term association between Page and Brin.

Initially, both had a difference of opinion over varied topics, but later, Larry's research thesis over search engine brought them together for the greater good.

Source: Google

In those days, most of the search engines, like Yahoo, were using keyword volume of any website as a ranking factor. But Page and Brin came up with a better search algorithm where they focused primarily on citations or backlinks from different websites. This was widely known as PageRank.

In the year 1996, the founder duo labelled their search engine as 'BackRub' since the ranking was solely depended on the number of backlinks from different websites. Soon, they realised the hidden potential and application of their newly developed search engine in the consumer market. In the year 1998, Google adopted the idea of selling search terms, aka ADs, from goto.com.

Google domain was registered on September 15, 1997. Although, Google Inc. was founded on September 4, 1998.

A major restructuring of Google took place on October 22, 2015, when an umbrella company ' Alphabet 'was born. As a result, Google's most ambitious and eccentric projects like driverless car & robotics (Boston Dynamics) including Google came under one banner. As on date, Larry Page is the CEO of Alphabet, whereas Sundar Pichai is the CEO of Google.

Let's capture all possible important dates & years which could be the possible contender for Google's birth.

• When the Google founders met - 1995
• When Backrub came into existence - 1996
• Google's domain registered - September 15, 1997
• Google Inc. founded - September 4, 1998
• Google came under Alphabet, an umbrella company - October 22, 2015

logically speaking, September 4 should have been the birthday as Google Inc. was founded on this date. The other possible option could be September 15, when its domain got registered.

There are a plethora of logic behind Google sticking to September 27, but the most logical reason could be that the first doodle which celebrated Google's birthday was on the same date.

Google has grown its stature by leaps and bounds. It started as a search engine giant, but now it has expanded its wings to various software and hardware businesses. Even regarding the revenue, Google is only next to Apple with 89.46 Billion USD (As per 31st December 2016 data).

It is not surprising to see why people are inquisitive to know the exact birth date of Google since there are so many different references. Do not be surprised if Google again changes its birthday in the coming years.