JavaScript Math Object

The JavaScript Math object allows you to perform mathematical tasks on numbers. Unlike other objects, the Math object has no constructor. All properties and methods of Math are static.

Math Properties (Constants)

JavaScript provides several mathematical constants that you can access via the Math object.

Math.PI — Approx. 3.14159
Math.E — Euler's number
Math.SQRT2 — Square root of 2
Math.LN10 — Natural logarithm of 10

Rounding Methods

There are 4 common ways to round a number to an integer:

Method	Description
`Math.round(x)`	Returns x rounded to its nearest integer
`Math.ceil(x)`	Returns x rounded up to its nearest integer
`Math.floor(x)`	Returns x rounded down to its nearest integer
`Math.trunc(x)`	Returns the integer part of x (removes decimals)

Other Common Math Methods

Math.pow(x, y)

Returns the value of x to the power of y.

Math.sqrt(x)

Returns the square root of x.

Math.abs(x)

Returns the absolute (positive) value of x.

Math.min/max()

Finds the lowest or highest value in a list.

Math.sign()

This method checks if a number is negative, null, or positive. It returns -1 (negative), 0 (null), or 1 (positive).

Math.sign(-4); // returns -1
Math.sign(0);  // returns 0
Math.sign(4);  // returns 1

Key Points to Remember

The Math object is static—no new Math() is required
Use Math.floor() for reliable "downwards" rounding
Math.PI is the most common constant for geometry calculations
Math.min() and Math.max() can take any number of arguments
Math.trunc() is safer for simply removing decimals than rounding
Mathematical functions help in creating graphics, physics simulations, and data analysis

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