Okay, so when you use a computer to type or send messages, there are certain special characters that you can use to do things like change the color of your text or move the cursor around. These special characters are called control characters.
Imagine your computer is like a big playground, and the control characters are like the teachers who tell you what to do. Just like how teachers might tell you to line up or sit down, control characters tell your computer what to do with the text or message you are typing.
For example, there is a control character called "backspace" that tells your computer to erase the character before the cursor. Another one is called "newline" that tells your computer to start a new line of text.
So overall, control characters are special instructions that you can use while typing on a computer, and they help you do different things with your text.