A Netscape Navigator plug-in is implemented in a dynamically linked code module. Microsoft designed the dynamic link library with an eye toward implementations such as a Netscape plug-in, but Netscape has taken a slightly different approach. Implementations are included for both types of APIs and how code is called.
More detailed documentation is continued throughout the next chapters.
If you scan through the plug-in documentation, you might notice that there are two types of APIs. These routines are implemented by your plug-in and are called from the Navigator. Plug-in Defined . These routines are implemented by the Navigator and are called from your plug-in. API Calling techniques.