Remaiten is a type of computer virus, which is like a bad germ that can make your computer very sick. Just like how you can catch a cold from being around someone who is sick, your computer can get a virus if you go to a bad website or open an email from someone you don't know.
Remaiten is a particularly sneaky virus because it can hide in your computer and make copies of itself so that it is very hard to find and get rid of. It can also do bad things like steal your personal information, slow down your computer, and even control it remotely without you knowing.
The good news is, just like washing your hands can help prevent you from getting sick, there are things you can do to protect your computer from getting infected with Remaiten. You can make sure to only visit safe websites, not open emails or attachments from unknown sources, and use antivirus software to protect your computer from viruses like Remaiten.