Okay kiddo, so you know how when we talk to someone, we use our mouths to say the words and the other person listens with their ears? That's called communication.
Now imagine you have a bunch of toys you want to give to your friends, but they're all far away from you. If you give one toy to one friend at a time, it will take a long time to give all the toys away.
Parallel communication is like having more than one mouth so you can talk to more than one person at a time. This means you can give all your toys away much faster because you're giving toys to more than one friend at the same time.
In computers, parallel communication means sending more than one piece of information at the same time through different wires or paths. This is faster than sending one piece of information at a time because it can be processed all at once instead of waiting for each piece to be sent separately.