So most of us प्रशंसकों know the song, "Disappearance of Hatsune Miku," right? Well, it wasn't just wrote for nothing. Read और if आप want to find out about the story.
A few weeks after Miku was released, her fame had grown to such a large scale that millions of people kept searching "Hatsune Miku" on Yahoo! and Google.
Yahoo! and गूगल thought that Miku was spam. So when a person would खोजिए 'Hatsune Miku,' it would lead them to no where. Which, in other words, means that आप would not be able to खोजिए 'Hatsune Miku' on Yahoo!, गूगल या YouTube.
The प्रशंसकों went crazy nuts, and so the song, "The Disappearance of Hatsune Miku" was created. Seeing the fans' rage because of their action, Yahoo!, गूगल and YouTube brought back Miku and apologized.
And so, that is why we celebrate 'Disappearance Day' every October. (I don't know the exact date)