The Laddoo Code


One morning, in Class 2B...
“Psst, Anjali! Pass this note to Ritvik,” whispers Rahul.

Anjali passes the note to Madhu.
Madhu passes it to Anwar.
Anwar passes it to Sanya.

And Sanya passes it to Ritvik.

Ritvik reads the note – Nani made laddoos!
Meet me behind the canteen.

But Anjali, Madhu, Anwar and Sanya have read it too.

“Laddoos!”

“Oh no, I don’t think we’re getting any...”

Everyone jumps on the laddoos.

Soon, there are no laddoos left.

The next day…
“Anjali, pass this to Ritvik, na?”

Anjali tries to read the note again, but can’t understand it.

Madhu can’t read it either. Neither can Anwar. Nor can Sanya.
But Ritvik knows exactly how to read it.

Ritvik wraps the strip of paper around his pencil, just the way Rahul did when he wrote it.
And the secret message is revealed!

Making and Breaking the Code
Rahul converts his message into a secret code so that no one else can read it. This method of protecting information is called encryption.
Ritvik wraps Rahul’s note around his pencil to reveal the message. This method of changing encrypted information back into plain text is called decryption.
Computers also use encryption and decryption to keep information safe.
Want to send secret messages like Rahul and Ritvik?
Wrap a strip of paper around a pencil and write your message on the wrapped paper. Then unwrap the paper and give it to your friend. Your friend can read the secret message by wrapping the paper around another pencil.