Functionality
Upon loading, a NLM requests resources, such as memory and process threads, from the NetWare kernel. The NetWare kernel tracks such requests, and can identify memory and other resources assigned to a specific NLM. NLMs may auto-load other NLMs upon which they themselves depend.
NLMs may register commands with the NetWare kernel, extending the command vocabulary available at the NetWare console prompt.
When properly coded, NLMs can be re-entrant, allowing multiple instances of the same code to be loaded and run.
Read more about this topic: Net Ware Loadable Module