Hey there! So, you know when you send an email to someone? Well, sometimes that email might bounce back to you because it can't be delivered to the person you sent it to. That's called a "bounce."
But sometimes, instead of bouncing back, your email might go to a different email address - one that you didn't send it to! That's called "backscatter."
Backscatter happens when someone sends a spam email, or an email that's trying to trick people into giving away their personal information. The email might use a fake email address that doesn't actually exist.
So, when your email tries to go to that fake email address, it can't be delivered. But instead of bouncing back to you, it goes to a different email address that's set up to receive these "reject" messages. That email address might belong to a person or a program that collects these messages to try and figure out where the spam is coming from.
So basically, backscatter is when your email gets sent to the wrong place because someone else sent a bad email first. It can be a bit confusing, but it's something that people who work with emails have to deal with!