Mirai is like a very bad bug that goes on computers and other devices like video cameras and makes them do bad things.
Imagine you have a bunch of toys in your room, and each toy has a button that tells it what to do. Mirai is like a sneaky person who comes in and presses all the buttons on your toys. This can make them start moving and making noises when you don't want them to.
In a bigger world, Mirai is a kind of computer program that infects devices like routers and video cameras. It does this by finding weak spots in their security and sneaking in. Once Mirai is inside, it can control the device and make it do things, like attack other computers or send spam emails.
Mirai is really bad because it can control a lot of devices all at the same time. This can cause big problems and make entire websites or networks stop working.
To stay safe from Mirai, you can make sure your devices have strong passwords and up-to-date security software. It's also important to be careful about what you click on or download, as Mirai can come in through these channels too.