Need to read: NONE
So, what is a number? Well, a number is an amount. It repersents an amount of things. If that be one thing, zero things, or a dozen. The most common way we represent numbers is with a set of 10 digits known as the the Arabic numerals (1, 2, 3, 4, 5, 6, 7, 8, 9, 0). But there are other ways, like tallies, roman numerals, or other bases. Other bases use less or more digits than the normal 10. Like binary (1, 0) or seximal (1, 2, 3, 4, 5, 0)
First, we have counting. We advance the count by one. Here is a sample of counting {567, 568, 569, 570, 571}. This makes much sense to almost all people, as it is quite simple. Something more advanced is known as backwards counting, as we get into number below 0. These are known as negative numbers, and you can see them on a section of the number line (Sorce: BYJU'S). Here is a sample of reverse counting {1, 0, -1, -2, -3}.
Now, we have addition. Think of it as repeated counting. So if we have the addition of 2 + 3, you start at 2 and advance (or count) 3 times forward (right) on the line to get to the answer of 5. But if you add using a negative number, you go the other way. So if you have 5 + (-6), you advance 6 spaces backwards (left) from 5 to get to -1. Subtraction is the opposite version of addition, where if you subtract a positive number, you go backwards, and if you subtract a negative number, you go forwards. An example of this is 4 - 6. You start at 4 and go 6 spaces backwards.
The last 2 opperations that you need to know about is multiplication and division. Multiplication is just repeated addition. So 3 * 4 is 3 + 3 + 3 + 3 or 4 + 4 + 4. But this only works for positive * positive and a negative * positive. With negative * negative, its different. You subtract the numbers so -2 * -3 is (-2) - (-2) - (-2) or (-3) - (-3). Its also good to think of multiplication as the total amount of things in X group of Y amount of things (X * Y). Division is how many group of Y size can you put X amount of things into (X / Y). So for example, 6 / 2. You can put 6 things into 3 group of 2. So the answer would be 3.
So those are the 4 (or 6 if you count the countings) basic arithmetic opperations, and from these basic opperations, we can find a new type of number which has many new interactions, fractions!