what different types of number 1 are there- explain each please?

Answer 1

That depends a lot on what class you're taking.

Strictly speaking, each number system (for example, the integers, the rational numbers, the real numbers, the complex numbers, and so on) has different elements, and in particular the element called "1" in each of them is different. Now, even professional mathematicians don't really think of those 1s as truly being different from each other. But there are other mathematical structures in abstract algebra where the difference is greater.

"1" is just the common name for the "multiplicative identity" element of a mathematical system -- i.e., the element such that, if you take E times 1 or 1 times E for any element E of the system, you just get E as an answer.

Any mathematical system that is a "field", "ring", or even just "group" will have such an element, and in many cases it's just called "1".

Answer 2

Little more clarification please...

Here's a start: It can be binary (0 or 1), where 1 is true. It can be an integer (-1 or 1).