It is important for web developers to know when JavaScript code is executed because it helps them understand how web pages and web applications work, and how JavaScript code interacts with HTML and CSS to create dynamic and interactive user interfaces.
By understanding when JavaScript code is executed, developers can optimize their code for performance, ensure that it runs at the appropriate time, and prevent issues such as race conditions or conflicts with other code on the page. They can also take advantage of features such as event-driven programming to create more responsive and interactive user interfaces.
In addition, understanding when JavaScript code is executed is important for troubleshooting and debugging issues that might arise in web pages or web applications. By knowing when and how code is executed, developers can identify and fix issues related to JavaScript code, and improve the overall user experience of their web pages and applications.
JavaScript code is executed when it is encountered by a web browser while parsing an HTML document. When a web page is loaded in a browser, the browser reads and parses the HTML code to construct a Document Object Model (DOM) representation of the page. As it encounters