The JavaScript Console provides two primary functions for developers testing web pages and applications. It is a place to:
• Log diagnostic information in the development process.
• A shell prompt which can be used to interact with the document and DevTools.
• You may log diagnostic information using methods provided by the Console API. Such as console.log() or console.profile().
• You can evaluate expressions directly in the console and use the methods provided by the Command Line API. These include $() command for selecting elements or profile() to start the CPU profiler.