Geometric meaning: On the number axis, the distance from the origin of a number is called the absolute value of the number. For example, the distance between the point on the exponential axis and the origin is 5, so the absolute value is 5. For example, the distance between the point on the exponential axis and the origin is 1.5, so the absolute value is 1.5.

Algebraic significance: the absolute value of a positive number is itself, the absolute value of a negative number is its inverse, and the absolute value of 0 is 0.

The absolute values of two opposite numbers are equal.

The absolute value of a is | a.

| "means. Read "the absolute value of a"

For example, |-2 | is read as the absolute value of -2.