The Workplace Shell provides a programming environment, in which suitably written programs can add user-defined object types to those provided with the system. Such objects may simply be modified versions of the supplied object types - such as a new type of folder that requests a password before the user is allowed to open it - or object types related to specific productivity applications, such as a spreadsheet object, or even object types that are specific to a particular user's business, such as Customer, Order or Motor Insurance Policy.
It has been found that a natural and productive way to implement this kind of user interface is to use object-oriented programming techniques. The Workplace Shell itself is written in this way, using a new component of OS/2 V2.0 called the System Object Model (SOM). SOM is a set of tools and APIs that allows object-oriented programs to be written in a mixture of programming languages, including languages that are not themselves object-oriented, such as C. All the Workplace Shell object types - folders, data files, printers, etc. - are implemented as SOM objects.