Google has called the development of Chrome its "big bet" for the future.
The search firm sees the software, in both browser and the operating system versions, as leading a major shift in how computers will be used.
The OS was inspired by the growing popularity of low-cost low-power netbooks and is targeted at users who spend most of their computer time on the internet.
Google's vision is one where users access everything from e-mail to photos and spreadsheets to documents via the cloud.
Industry watchers have said Chrome is clearly meant as a threat to Microsoft which makes the bulk of its profits from selling its OS and Office software for use on desktop PCs.
"This is as big as they come," said Linus Epson, vice president of engineering for Chrome.
"Windows and Mac have dominated the OS landscape for a long, long time," he said. "Lots of people have tried and not succeeded so this is a once in a working career type of opportunity and problem to go after."
For Sundar Pichai, head of Chrome development, Google's aim is to shake up the industry.
"If you came from outer space you wouldn't design the computer the way it is today," he said.
"I think there is an opportunity to make computing much more delightful and simplified all the way from an advanced to a novice user. That is where the opportunity is and that is where the gauntlet gets thrown down.
"We wouldn't be doing anything if we didn't believe we could change the computing landscape," said Mr Pichai.
The bid to change the computing landscape started with the Chrome browser which was first released in September 2008.
For years Google boss Eric Schmidt was against the idea of building an independent web browser. At the time he said Google "was a small company" and that he did not want to get locked into a "bruising browser war".
Back in 2008, Microsoft's Internet Explorer dominated the web world with almost 68% of the market. Firefox was second with nearly 26% according to research firm StatCounter.
Since 2008, Chrome has grown to have more than 12% of the market while IE has lost ground. Its share stands at around 49% while Firefox has more than 31%.
Mr Pichai said for engineers like him, creating a browser from the ground up made good sense.
"If you step back and think about what Google does, it is all on the web," he said. "Almost all our users use our services through a web browser. Most of the money we generate are on web properties consumed on a web browser so in some ways the browser is one of the most important platforms we can work on."
He said the the old model typified by Microsoft was too cumbersome for many modern users.
"The PC is a legacy of how things have worked for the last 30 years in software," he said. "If tomorrow you were to come and start from scratch you would make a very different set of assumptions about what it is about."
"I consider myself to be a very sophisticated user of computers and it is extremely painful for me if I buy two PCs I have to make sure they are on anti-virus software. I have to make sure I install the same software so that I can go back and forth.
He said: "I don't have time to do all that and I think there is a far greater and simpler possibility and that is what this journey is all about."
The browser is just half the Chrome story. The other half is the operating system.
"The OS is a natural evolution for us in the sense of when we built Chrome itself, the simple bet behind it was a web that had shifted from documents to applications," said Mr Pichai.
"People are living and using these apps on the web and so we viewed it as how do you build a modern browser which ran those apps," he said. "It is mainly understanding that users are living on the web and creating a computing experience to reflect that.
"Chrome OS is the next step in that evolution," added Mr Pichai.
One of the main challenges the team faced was undoing decades of behaviour which left people familiar with loading computers with software, features, files and documents.
Chrome means stripping everything back to the bare essentials to speed up the computing experience.
"By not having any files on your computer and having everything synched to the cloud, your machine is a lot faster," said Mr Epson. Early demos of Chrome in November 2009 showed a notebook booting up in seven seconds.
"Once we take away that constraint of we have to run on your legacy computer then that allows us to simplify things dramatically," he said.
"The big advantage that we had was that the model that the PC has lived in for the last 30 years has a lot of baggage in it that isn't relevant anymore," said Mr Epson. "So by making this clean break (with our own OS) we are not encumbered by all the compatibility issues."
When Google first talked about Chrome, low cost notebooks were all the rage. Today the focus is on more mobile devices like tablets, a market that has been re-ignited since early 2010 by Apple's iPad.
The tablet is the natural home for the Android operating system which powers a multitude of smartphones and has given Apple's iPhone a run for its money.
The existence of two Google OSes has led some to wonder if both are needed.
Speaking at the web 2.0 Summit in November, Google boss Eric Schmidt is in no doubt that they are. Largely, he said, because they do distinctly different things.
Chrome OS is being developed for devices with physical keyboards while Android is for touch devices.
Industry watchers have said that with a growing appetite for tablets, Chrome may have already lost out to Android.
Mr Pichai disagrees.
"We come from a simple belief that if you can create a great experience for users the market follows from that," he said.
"What the iPad validates to me is that people are looking for what I call different computer alternatives," he said. "No-one lives with the iPad as their only computing device. But it has created excitement around additional computing and we plan to do the same."
Notebooks running Chrome from the likes of HP, Acer and Asus were expected before Christmas but have now been delayed until 2011.
The reason for the delay is very simple, said Mr Pichai.
"We aren't fully ready yet," he admitted.
"We started working on this 18 months ago and we have made tremendous progress but we aren't all the way there," he told BBC News. "There are still some features we want to add and also the system still has some crashes and bugs we need to resolve before we ship it out."
"It is more of a traditional beta software quality at this stage," he said. "When we ship, we want to ship a finished consumer product."
So has Google bitten off more than it can chew and is the public ready for computing that relies so heavily on the cloud?
"It requires a change in thinking about it," said Mr Epson. "We are doing something that is pretty different than what's happened before and whenever you do that it takes people some time to adjust.
"That is the biggest thing we have had to overcome and will continue to have to overcome," he said.
Google believes its entry into a mature market will present challenges for its competitors but most importantly choice for consumers.
"For us success means being able to reach tens of millions of users over time, so we expect this to have an impact," said Mr Pichai.
"I don't think of it as throwing down the gauntlet. I want to raise the bar and Chrome did that in several areas of browsing and with Chrome OS you will see us raising the bar significantly.
"The key challenge has been time," he said. "I wish we had more time.
"What keeps me up at night is we are entering the PC space in which people have 30 years of legacy expectations where old habits die hard," he said. "We are worried people will stick with the safe and familiar and comfortable but confident that if people used Chrome for a week or two they would choose that."