The first. io games was called "Agar.io." Matheus Valadares, a 19-year-old coder from Brazil, made it. In 2015, he announced it on 4chan. 

In the online team game Agar.io, you play as a cell that needs to eat smaller cells to stay alive as long as possible. There are also bigger cells you have to stay away from or you'll be eaten! The game was a big hit because the job was easy but hard.

PewDiePie, a popular YouTuber, talked about the game in one of his shows a month after it came out. The movie was seen by more than 8 million people. This made the game famous all over the world and brought attention to the.io games genre. 

After Agar.io was a hit, many more.io games were made quickly, and since then, the fame of this type of game has grown.

Why do so many people play io games?

io games became famous because they were easy to understand and play. The genre is very popular because you don't have to download the game to play it and you don't have to do lessons to understand it. Because io games were easy to play, they could be played on almost any device, which gave them a bigger audience.

Every.io game has a multiplayer mode, which pushes games as ways to meet new people. The growth of.io games was also helped by the fact that there are so many different ones. Everyone can find a.io game that they like, from shooting games to games that let you explore and make your own. 

Livestreaming was another thing that helped make this type of game more famous. Since PewDiePie's videos about Agar.io got millions of views, many other YouTubers and game live streamers have made a lot of content about io games, which has made them even more famous.