Here is a list of all documented namespaces with brief descriptions:

[detail level 1234]

Nfpsdk	Fixposition SDK
Napps	Fixposition SDK: Apps
Nfpltool	Fpltool
Nparsertool	Parsertool
Nstreammux	Streammux
Ntimeconv	Timeconv
Ntimetool	Timetool
Ncommon	Fixposition SDK: Common library
Napp	Utilities for apps
Ncan	CAN bus utilities
Nfpl	.fpl utilities
Ngnss	GNSS types and utilities
Nlogging	Logging
Nmath	Math utilities
Nparser	Parser
Ncrc	Parser NOV_B routines and types
Nfpa	Parser FP_A routines and types
Nfpb	Parser FP_B routines and types
Nnmea	Parser NMEA routines and types
Nnovb	Parser NOV_B routines and types
Nqgc	Parser QGC routines and types
Nrtcm3	Parser RTCM3 routines and types
Nsbf	Parser SBF routines and types
Nspartn	Parser SPARTN routines and types
Nubx	Parser UBX routines and types
Nunib	Parser UNI_B routines and types
Npath	File and path utilities
Nros1	ROS1 types and utils
Nstring	String utilities
Nthread	Thread helpers
Ntime	Time utilities
Ntrafo	Transformation utilities
Ntypes	Common types
Nutils	Utilities
Nyaml	YAML utilities
Nros1	Fixposition SDK: ROS1 library
Nbagwriter	ROS1 bag writer
Nmsgs	ROS1 messages
Nutils	ROS1 utilities
Nros2	Fixposition SDK: ROS2 library
Nbagwriter	ROS2 bag writer
Nros1	ROS2 types conversion from ROS1
Nutils	ROS2 utilities