AIM, the chat service that ruled the '90s and the early 2000s, is dead. AOL’s parent company Oath has announced that it would be retiring the service (which, to be honest, we didn’t realize was still kicking), sending that yellow running man off into the sunset on December 15, 2017. In fond remembrance of the pre-social-media days when the beeps and door-shutting sound effects of AIM were the soundtrack to procrastination everywhere, here are seven facts about the pioneering chat service:

1. IT STARTED OFF AS AN OFF-THE-BOOKS COMPANY PROJECT …

IM-ing had long been a part of AOL’s functionality, but in 1996, a very small group of AOL employees began working on the idea of a free (remember when you paid for AOL?) standalone messaging service. They didn’t pitch the idea to AOL’s executives, and worked on the project unofficially using servers that someone at the company’s data centers had “lost,” as the engineers who started the project told Mashable in 2014. Once it was added to AOL’s public servers, AIM was an instant success, despite the fact that you had to download it directly from a server address—there wasn’t even a webpage for it. By 1999, it had 40 million users and was the “de facto standard for instant messaging over the Internet,” according to The New York Times. In 2003, it was handling about 2 billion messages a day.

2. … AND SOME OF ITS MOST ICONIC FEATURES WERE LAUNCHED WITHOUT COMPANY APPROVAL.

The engineers who had created AIM as an under-the-radar project were also quick to update it without permission from up the chain. This process led to some of the system’s most iconic features, including the buddy icon. Despite the massive successes of the software, the corporate overlords at AOL never quite got behind it, in part because they couldn’t come up with a way to monetize it that fit with the rest of the AOL subscription service.

3. IT CHANGED THE WAY PEOPLE TALKED ONLINE.

AOL offered its users a built-in selection of 16 smiley faces in the late '90s, according to CNN. And then there were the LOLs. In a story on AIM and teens in 2003, The New York Times wrote, “In fact, instant messaging has become an unofficial dialect, and devising misspelled versions of words lacking as many vowels as possible has become a literary form.”

4. IT WAS DESIGNED TO LET PEOPLE CHAT AT WORK, WHETHER THEIR BOSSES LIKED IT OR NOT.

According to Mashable’s 2014 history on the subject, programmers working on AIM “made the program the bane of IT departments.” The engineers were focused on consumers, not their irate bosses, and created features in the software that allowed it to circumvent network blocks, allowing users to ROFL about their bosses unimpeded.

5. IT WAS AT THE CENTER OF A TECH FEUD.

In the late 1990s, AOL fought hard to keep competitors from getting in on the instant-messenger game, and refused to make its software open to outside developers. Both Microsoft and Yahoo tried to create software that would allow their users to see and communicate with AIM users—like how you can send an email to someone even if you’ve got an Outlook account and they use Gmail. AOL was not happy, and blocked the software immediately. Microsoft responded by tweaking MSN Messenger to get past AOL’s block. AOL blocked it again. According to AIM creator Eric Bosco, the two companies went through the same dance 21 different times before Microsoft gave up. For what it’s worth: MSN Messenger shut down in 2014.

6. IT COULD HAVE BEEN THE NEXT NAPSTER.

Another intriguing tidbit from Mashable’s interviews with AIM’s creators: AOL engineers tried to give the chat software capabilities similar to the infamous file-sharing service Napster. They called the project “Aimster” internally, creating functions where users could search their friends’ files and transfer them to their own computers. It never made it out of the development phase. (There was, actually, a file-sharing service called Aimster founded in 2000, but AOL sued the company for copyright infringement, forcing it to become Madster.)

7. IT INFLUENCED GCHAT IMMENSELY.

Unsurprisingly, AOL’s pioneering chat service made a huge mark on the instant messaging of today. Justin Uberti, a lead software architect for Google messaging apps, had also played a large role in AIM. “You can definitely see the influence of the early work that Justin did,” Bosco told Digital Trends in 2016. “You can see a lot of that taking shape in some of the Google offerings.”