Interact across browser javascipt and unity webgl

Hi all,
I have a scenario where i have a website in which user registration,signup and signin processes are done.And then user clicks a button in that website and my webgl gets loaded in another i want to know the user details that he had entered in that other webpage in unity webgl loaded scene.How do I communicate.Please suggest or point me in right direction.Iam new to unity webgl.
Thanks in advance.

I manged to solve the issue easily by simple adding sendMessage ('MyGameObject', 'MyFunction', 'example'); in the script “unityloader.js”.
Also i called javascript methods from unity by simply calling Application.ExternalCall("MethosinJavaScript") ;
Thank you guys.

Calling between JavaScript code from Unity

You can use the Application.ExternalCall() and Application.ExternalEval() functions to invoke JavaScript code on the embedding web page. To call methods on GameObjects in your content from browser JavaScript, you can use the following code:

sendMessage (‘MyGameObject’, ‘MyFunction’, ‘example’);