Browser Helper Object

: Browser helper objects were first introduced in 1997, along with Microsoft Explorer version 4.0. When Internet Explorer is started, these objects are typically loaded once per session. On the other hand, when Windows File Explorer is started, a new BHO session is launched for each window. A BHO may consist of many different plugin modules, all of which may display different file formats that are not regularly translated by the browser. A clear example would be the Adobe Acrobat module that enables Internet Explorer users to open and read PDF files within the web browser. BHO implements other modules to Explorer, such as the Alexa Toolbar, which offers users a comprehensive lists of sites with coinciding themes to the one currently be viewed. It may also add a Google Toolbar, which not only acts as an additional toolbar, but also provides the Google search box to the browser’s interface.