Ten years of Gmail

I don't remember my first email message. It was some time during the early 1980s when I was working at DEC. For most of that decade, email was all internal, sent from one DEC-owned computer along DEC networks to another DEC-owned computer.
As the 80s closed, there were a bunch of email protocols and messaging schemes. It wasn't until the early 90s that I started using the name@company.com format on a regular basis.
My first non-work email address was through a local provider, now defunct, called iii.net (It's now a parked domain held by a Chinese company.) It was run by a weird, fanatically pro-smoking guy named Joe Something-or-other whom I knew from DEC. We used that for a couple of years and then switched to Ultranet before buying my own domain and hosting services in 2001.
When Gmail came along in April 2004, it was invite-only. Google handed out invitations to a few folks and let those new subscribers invite others. It took until August for someone in my circle of friends to have invitations available. I signed up on August 25, 2004.

They promised a gigabyte of free storage, five to 10 times what other providers were offering. They discouraged people from deleting messages. They did this in part so that they could have more information to search and thus give you ads and also to change our thinking about online storage. Cloud storage is, for most folks, effectively unlimited. I long passed 100K messages. (At this writing I have 113,481 conversations, individual messages plus replies. I am using 11Gb for email and other Google services such as photos and docs.
Threaded messages were confusing to some people at first. In threaded email messages, the original messages and its replies are grouped together. It's much easier to keep track of discussions, but it can be disorienting for people who were expecting each email to be delivered in a discrete chunk.
Some of my friends distrust Google and/or cloud services and prefer to download all of their email to their local computer. Others dislike the Gmail interface, the appearance of ads, and Google in general. Good for them.
For me, the convenience of having an email service that I can use on any device anywhere far outweighs the worries.
Gmail changed the way that we think about email. No other product has come close to having that kind of impact.