If you don’t know what the program does from the name then you’re not in the target audience, but essentially it scans all the running processes on your system, detecting and listing whatever DLLs they’re using. The usual NirSoft table includes plenty of information for each DLL: its name, type , product name and version, file description and version, company, path, file created/ modified times, file size and the total number of processes using that DLL.