Editing IBM System Object Model (section)

{{short description|Programming framework}}
{{distinguish|System Object Model (file format)}}
{{Refimprove|date=March 2013}}
{{Infobox software
|name           = IBM SOMobjects
|logo           = IBM System Object Model Logo.png
|logo alt       = IBM SOM Logo
|screenshot     = <!-- Image name is enough -->
|caption        =
|screenshot alt =
|developer      = [[IBM]]
|latest release version = 3.0
|latest release date = December 1996
|operating system = [[OS/2]], [[Microsoft Windows|Windows]], [[AIX]], [[Classic Mac OS]], [[Copland (operating system)|Copland]], [[OS/390]], [[NonStop OS]], [[OS/400]]
|genre = [[Object-oriented programming|object-oriented]] [[shared library]] system
}}

The '''System Object Model''' ('''SOM''') is an [[Object-oriented programming|object-oriented]] [[shared library]] technology developed by [[IBM]] that supports defining an [[interface (computing)|interface]] to an [[object (computer science)|object]] so that its interface is separate from its [[implementation]]. 

'''DSOM''', a [[Distributed computing|distributed]] variant based on [[CORBA]], allowed objects on different computers to communicate.

A SOM library can be updated without requiring client code to be rebuilt. If a library is changed to add new classes or methods, or to change the internal implementation of classes or methods, a consuming program can still use it without being rebuilt. In this way, SOM addresses the [[fragile binary interface problem]] that affects other library technology such as [[C++]].

SOM allows [[class (computer science)|classes]] to be defined in one [[programming language]] and used in another. A client can create and use objects from the exposed classes and derive subclasses from the exposed classes even if the client language does not support class typing.

SOM provides an [[application programming interface]] (API) that provides access to library [[metadata]]. Each object exposes methods that provide the class name and whether the object implements a particular method, for example.