ELENA API consists of modules (files with .NL extension) containing classes and symbols. Every class or symbol may be referred by its namespace (or to put it other way around a symbol namespace is a path to the symbol module).
All source files (files with .L extension) located in the same folder are compiled into the corresponding module. A project file (a file with .PRJ extension) defines the root namespace and the output type (stand-alone executable, VM executable or a library). The project may produce several modules if it contains the files located in sub folders (the new module namespace consists of the root one plus the folder relative path)