How Gmail Happened
If you wanted to pick a single date to mark the beginning of the modern era of the web, you could do a lot worse than choosing Thursday, April 1, 2004, the day Gmail launched.
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Within Google, Gmail was also regarded as a huge, improbable deal. It was in the works for nearly three years before it reached consumers; during that time, skeptical Googlers ripped into the concept on multiple grounds, from the technical to the philosophical. It’s not hard to envision an alternate universe in which the effort fell apart along the way, or at least resulted in something a whole lot less interesting.