Displaying Output in Alert Dialog Boxes

You can also use alert dialog boxes to display the message or output data to the user. An alert dialog box is created using the alert() method. Here's is an example:

During these formative years of the Web, web pages could only be static, lacking the capability for dynamic behavior after the page was loaded in the browser. There was a desire in the burgeoning web development scene to remove this limitation, so in 1995, Netscape decided to add a scripting language to Navigator. They pursued two routes to achieve this: collaborating with Sun Microsystems to embed the Java programming language, while also hiring Brendan Eich to embed the Scheme language.

Writing Output to the Browser Window

You can use the document.write() method to write the content to the current document only while that document is being parsed. Here's an example:

If you use the document.write() method method after the page has been loaded, it will overwrite all the existing content in that document. Check out the following example:

Inserting Output Inside an HTML Element

You can also write or insert output inside an HTML element using the element's innerHTML property. However, before writing the output first we need to select the element using a method such as getElementById(), as demonstrated in the following example: