On April 1, 2004, Google launched Gmail and almost immediately changed the way people use email.
Gmail accomplished the tricky feat of staying ahead of the competition technologically while growing to become the world's largest email service.
Boasting more than 500 million users, Google's(GOOAV) mail service is much more than a service to many, it's damn near a religion. (For proof of that, just look at the status updates on any social network during a Gmail outage.)
But Gmail wasn't born in pioneering days of email, nor was it the first email service to go mainstream. So why is so dominant now?
For years, Gmail blew rivals out of the water with the entire gigabyte of storage it offered. When Yahoo(YHOO) was finally forced to react, it offered a measly 100 megabytes in response.
Gmail's search was a revelation. Having the power of Google's Web search in your inbox not only made life easier, but it legitimately saved time.
But Gmail didn't just cruise on the momentum of having a game changing product. Gmail maintained its status as the most innovative even after attaining monolithic status.
Gmail took the mobile experience seriously even before Apple's(AAPL) iPhone existed. It added user-centric features, such as auto-save for unfinished emails and the priority inbox, which automatically surfaces only the most important emails. And most importantly, it has integrated Gmail with the rest of Google's services.
Google's chat, calendar and productivity apps began as part of Gmail. In the days before Android, Chrome and apps, Gmail was the intersection for all things Google -- even more than the search engine itself.
Gmail has never been a static product, and updates come both as a stream of little fixes or big rollouts of major new features. This has been as important as anything in keeping Gmail in good standing with its users. It never feels dated and it never feels lacking.
And when Google realizes that users despise some aspect of the service, it hasn't been scared to make changes.
That said, Gmail's 10 years haven't been without its rough patches. Gmail's redesigns haven't always been well received, and the new tabbed inbox that filters out listserv and promotional emails have confused some users.
Privacy has also been a concern, especially with Google's disastrous attempt in February 2010 to launch Buzz, a social network within Gmail. Google also bungled a change to its terms of service in 2012, which redefined the way in which it can use the data it collects via Gmail and other apps.
But to Google's credit, it has at least tried to be transparent about what information it collects from Gmail and how it advertises to users.
Have services such as Microsoft(MSFT) Exchange and BlackBerry(BBRY) Mail offered greater reliability and security? Yes. But Gmail has been catching up -- and it offers more features that everyday email users care about.
Email is arguably the least pleasant part the internet. That Gmail has made that experience exponentially less dreadful says a lot about why it's so integral to many of our lives.