0 is the smallest complete square number. This is a real number. 0 is an even number. 0 is the smallest natural number.

Junior high school:

0 is neither positive nor negative.

0 is neither positive nor negative, the opposite of 0 is 0, and the absolute value is itself.

0 times (dividing) any real number equals 0, and any real number plus 0 equals itself.

0 has no reciprocal and negative reciprocal, a non-zero number divided by 0 has no meaning in the real number range, and 0 divided by 0 has infinite solutions.

The positive power of 0 is equal to 0, and the negative power of 0 is meaningless.

0 has no power of 0.

0 cannot be the true base of logarithm.

The zeroth power of any nonzero real number is equal to 1.

0 occupies a position in a multi-digit number. For example, 0 in 108 means that there is no tenth place, so you must not write 18.

0 cannot be used as a multi-digit most significant bit.

When 0 is not before other numbers, it means a valid number.

The factorial of 0 equals 1.

0 is always the origin of the coordinate system.