Bomba is like a secret code that you use to keep your messages safe from bad guys who might try to read them. It's like when you have a special word with your friends that only you know what it means, so no one else can understand what you're saying.
In cryptography (which is a big word that means secret codes), a bomba is a way to change your messages so that only the person you want to read them can understand them. It's like turning your words into a secret language that only you and your friend can speak.
To make a bomba, you start with a key (which is like a magic key that only you have) and some letters or numbers you want to send as a message. You use the key to mix up the letters and numbers in a special way that only you and your friend know how to do. Then you send the mixed-up message to your friend.
When your friend gets the mixed-up message, they use the same key to un-mix the letters and numbers back into the original message. This way, only you and your friend can read the message, and no one else who might want to read it can understand it.
So, a bomba is a way to keep your messages safe from people who might try to read them without your permission. It's like having your own secret language that only you and your friends can understand.