Call collision is like when two people try to talk at the same time and no one can understand what they are saying. Imagine you are playing with your friend and you both want to say something at the same time, but you can't hear what the other person is saying. That is a collision.
In a phone call, if two people try to talk at the same time, it can create a problem called call collision. This is when you may hear some strange noises, like beeps or static, and you can't understand what the other person is saying. It can also cause the call to drop, which means that the call abruptly ends before you finish talking.
This happens because phone lines can only handle one conversation at a time. If two people try to talk at the same time, the phone line cannot transmit two signals simultaneously, and the result is a call collision. This is why it's important to be patient and take turns when talking on the phone, so you don't run into this problem.