String Methods - JavaScript Tutorial - w3Schools - Chapter-17 English

String methods help you to work with strings.

String Methods and Properties
Primitive values, like "John Doe", cannot have properties or methods (because they are not objects).

But with JavaScript, methods and properties are also available to primitive values, because JavaScript treats primitive values as objects when executing methods and properties.

JavaScript String Length
Extracting String Parts
Replacing String Content
Converting to Upper and Lower Case
JavaScript String Padding
Extracting String Characters
Converting a String to an Array