A representation of a value in math. 0 represents nothing and 1 is the first positive number. A way of noting them down is a numeral system.
-1 0 1 | | | positive | number negative number
Five most important numbers in math: 0 (basis of algebra), 1 (basis of all real numbers); i (basis of imaginary numbers), e (basis of exponential functions), pi (necessary for circles)
0
A primary number. Neither positive nor negative, lies on the boundary. Multiplying anything by 0 gives 0. Dividing by 0 is not defined.
1
An odd number. Multiplying anything by 1 results in the original amount.
π
Circle's circumference/diameter - 3.141592653589...
Euler's number - 2.27...
∞
Infinity is the mathematical concept of a quantity so unimaginably large that it has no end. The symbol for infinity is a sideways 8 (unicode character U+221E). It implies "always having more new things". From certain perspectives, it is the opposite of 0, the smallest quantity. It could be argued that potential infinity is the reason for the existance of high level mathematics, as the infinite number of possibilities are what forces people to write mathematical proofs as opposed to thoughtlessly checking solutions. One could say infinity is not a number but an entirely different concept that is only related to numbers.
There is potential infinity (something with no upper limit) and actual infinity (infinity as a tangible object). There is also countable infinity (an infinite set of numbers) and uncountable infinity (infinite sets of infinite numbers).