Subtraction is a way to find out how much more one number is than another number.
Think of it like having a pile of blocks and taking some away. If you have 9 blocks and you take away 4 blocks, you can use subtraction to find out how many blocks you have left.
Here's an example:
9 - 4 = 5
The answer, 5, is the number of blocks you have left when you subtract 4 from 9.
The symbol - is used to show subtraction. You can subtract as many numbers as you want, just keep subtracting one number from the next! With a little practice, you'll be subtracting like a pro!