That is, it presents many things to you as objects, and lets you manipulate them as such. For example, you can refer to the current window as window or the current document as document . The pieces of information associated with an object are called the properties of that object. To refer to a property of an object, you use the name of the object, a period, and the name of the propety. For example, you can obtain the title of a document as document.title .
Objects also have associated functions, which are normally called methods .
These are the things that the object knows how to do. For certain types of predefined objects, such as windows and arrays, you create a new object using the new command. Unlike many languages, JavaScript supports only untyped variables. You can use the same variable to store some text, a number, or an object. You assign values to variables by writing the variable name, an equals sign, and the expression you want to assign to the variable.