In fact in many cases evolved standards are implemented to ensure the systems run the selected software for your company. Reasons for using an intranet within a company range from providing online assistance for a product support group to workgroup collaboration on documents databases and other shared environments. By installing an intranet you can create shared environment by allowing more people access to the information they need to succeed at their jobs. In the product support example you can implement systems that mimic applications that are supported without actually installing those applications. By showing diagrams screen shots and other information and then mapping that information to a knowledge base database the intranet quickly becomes a key player in supporting the technicians that support your customers.
Intranets offer some advantages regarding configuration as well.
Since you know the configuration of the systems on your internal networks you can begin to use some specific tools to provide information to your user base. For example on the World Wide Web it's not very feasible to offer information in a solely Microsoft Word format without also providing that information in other formats. Because you are unfamiliar with the tools available to someone browsing your Web pages you need to make sure your content is available to the lowest common denominator. Using an intranet you're free to distribute information by using those tools most likely to reside on a user's desktop system. This means if the source document is in Microsoft Word format you can post the Word document as-is without converting it to HTML or text format.