Browser Object Model

  • The  Browser Object Model (BOM) is a larger representation of everything provided by the browser including the current document, location, history, frames, and any other functionality the browser may expose to JavaScript. 
  • The Browser Object Model is not standardized and can change based on different browsers.
  • The BOM's most important task is managing browser windows and enabling communication between the windows. Therefore, the window object stands at the center of the BOM.
  • Every HTML document loaded into a browser window becomes a Document object which is an object in the Browser Object Model (BOM).  All nodes with their contents in the BOM can be modified or deleted, and new node can be created by Javascript.



  • The Document Object Model (DOM) is standardized and is specific to current HTML document. It is subset of BOM.
  • BOM is the catch-all category of JavaScript. There are many objects, methods, and properties that are not part of the DOM structure. For example, the URL of the current page or the identification string of the browser are defined on the window object.

BOM Reference