When a number has no indication of sign, by convention, it is assumed to be positive. In some cases, the plus sign (+) is used to emphasize that a value is positive, not negative. When using the + sign to indicate that a value is positive, make sure that it is clear, so as not to cause confusion as to whether the value is positive, or whether the operation of addition is involved.
The following number line can be used to represent positive numbers:
The blue ray shown on the number line represents positive numbers. It does not include 0, but unlike integers, includes fractional components of numbers. The numbers on the left of 0 on the number line are the negative numbers.
One way to conceptualize positive and negative numbers is to think of positive numbers as possessing something, be it pieces of candy, money, or something else. If you have 1 piece of candy, you have a positive number of pieces of candy. If you have no candy, you have 0 pieces of candy, and if you owe some candy to a friend, you can think of it as having negative amounts of candy; until you give your friend the candy you owe, you have less than 0 pieces of candy since any pieces of candy you get should go to your friend.
Is 0 positive or negative?
Zero is neither positive nor negative. Numbers can either be negative, positive, or zero. Zero is in a category of its own.
Positive numbers are defined as any number that is greater than zero. Negative numbers are defined as any number that is less than zero. As such, neither positive nor negative numbers can be defined without zero being in a category of its own. One way to think of this is that the number, 0, can neither be greater nor less than itself, so it cannot be positive or negative. "Non-negative numbers" include all positive numbers and zero, not just positive numbers.