ObjectARX
From Wikipedia, the free encyclopedia
ObjectARX (AutoCAD Runtime Extension) is an API for customizing and extending AutoCAD. It provides access to a class-based model of AutoCAD drawings and interactions with the AutoCAD user. There are two related current versions of the API; one is for C++ for native compilation, and the other is for the .NET platform, though AutoCAD objects in the .NET version are not garbage collected.
ObjectARX is a set of classes and functions used to extend Autodesk products by which you can customize your CAD application from Autodesk. IntelliCAD has also introduced a variant of ObjectARX which is currently being tested.
They are applications which can be used to customize your needs and perform a lot of complicated operations and repetitive tasks in a lot less time.

