The `Math.sqrt()` method is a built-in method in Java that calculates the square root of a given number.
Related terms
Return type: The return type refers to the data type of the value that is returned by a method. In the case of `Math.sqrt()`, the return type is `double`.
Built-in method: A built-in method, also known as a predefined or library method, is a function that comes with a programming language and can be used without needing to write its implementation code. Examples include `Math.sqrt()`, which is part of Java's standard library.
Square root: The square root is a mathematical operation that determines what number multiplied by itself equals another given number. In this case, `Math.sqrt()` calculates the square root of a given number.