Deferred scripts are the scripts whose statements run as grouped together statements as a function. Function provides a definition of a block that a script statement consists of to run the statements that are in the <SCRIPT> tags after all the statements loaded in the browser. Functions allow to see the user clearly the visiblity inside the <SCRIPT> tag. In this tag each function starts with function() and function name is written after it including the parentheses. Once a function is loaded it becomes ready to run whenever there is a use of it. It is useful when a function gets used immediately after a page load. The Window object uses an event handler that triggers the response to the user actions and the handler is onLoad.