JavaScript Execution Order

Which piece of JavaScript runs when?

To someone experienced with using JavaScript it is really obvious which parts of the code will be run at what stage in the processing of the page source in loading the page and subsequently as a result of interactions by the visitor. To someone who is just starting out it may not be anywhere near as obvious (particularly given that well written JavaScript is kept completely separate from the HTML). In this article we look at the different types of code fragments that can be found within any JavaScript and look at which parts of it get run when.

JavaScript Execution Order