Some firsts are historic and widely known, like the Wright Brothers’ first flight, Neil Armstrong’s first step on the moon, Edison’s light bulb, and Alexander Graham Bell’s first phone call.

Most firsts, even when they signal the introduction of important new technologies or trends, are relatively unknown to the general public. Let’s look at a few.

1. The First Tweet

The first Tweet was sent by Jack Dorsey, the co-founder and long-time CEO of Twitter, on March 21, 2006. Here it is:

Not the most interesting tweet for being the first. I wonder if Dorsey wishes he’d tweeted something more creative for his first tweet, like “Do you ever feel like you’re living in a simulation?” or “I’ve spent all morning trying to work out the square root of negative one by hand and it’s not going well.”

2. The First Email

Ray Tomlinson invented email in 1971 and in so doing transformed the @ symbol from rarely used to what the Museum of Modern Art called “a defining feature of the computer age.” Tomlinson sent the first emails to himself (from one computer to another). Unfortunately, there was no Alexander Graham Bell moment like “Mr. Watson, come here — I want to see you” for the first email. Tomlinson said he can’t remember what the first email message was.

In 1996 I sent my first email. I was a young lawyer at a big law firm and a New York lawyer asked me to email him a brief. I had no idea how to send an email, so I went to our firm’s law library and asked our librarian. Our firm of over 200 lawyers had a single email account. Greta, the librarian, showed me how to log in, attach the file, and send the email. Then, I called the NYC lawyer to make sure he got it. LOL. I thought sending the email was cool, but didn’t imagine its ubiquity and how it would transform all our lives.

3. The First Book Purchased on Amazon

Amazon is now known as the “Everything Store,” but it started merely as an online bookseller. The first book purchased by a non-Amazon employee was by John Wainwright, a computer scientist that was given a link to beta-test Amazon’s fledgling website. The book he bought on April 3, 1995 was Douglas Hofstadter’s Fluid Concepts and Creative Analogies: Computer Models Of The Fundamental Mechanisms Of Thought. Decades later Wainwright said that first purchase was still in his order history.

In honor of that first purchase, Amazon has a “Wainwright Building” on its campus (not to be confused with this Wainwright Building, which some claim to be the first skyscraper).

4. The First eBay Item Purchased

In 1995 Mark Fraser was a salesperson, and his job included making a lot of presentations. He really wanted a laser pointer but didn’t want to shell out the over $100 they cost at the time. He tried to get his employer to buy him one, but they refused. He was handy and liked to tinker with electronics, so he thought if he could get his hands on a broken laser pointer, he might be able to fix it.

The internet in 1995 was still in its early days — there were only 35 million users (which is just 0.6% of the global population). In 1995, eBay was a startup and was called Auction Web. Pierre Omidyar, eBay’s founder, listed a broken laser pointer on the new site, and somehow Mark Fraser found the listing and bought the broken pointer. That was the first sale on eBay.