One of the first methods of interprocess communication in Windows was Dynamic Data Exchange (DDE),[4] first introduced in 1987,[5] that allowed sending and receiving messages in so-called "conversations" between applications. Antony Williams, who was involved in the creation of the COM architecture, later distributed two internal papers in Microsoft that embraced the concept of software components: Object Architecture: Dealing With the Unknown – or – Type Safety in a Dynamically Extensible Class Library in 1988 and On Inheritance: What It Means and How To Use It in 1990. These provided the foundation of many of the ideas behind COM.