Here is a list of all files with brief descriptions:

[detail level 1234]

include
librealsense2
h
rs_advanced_mode_command.h	Advanced Mode Commands header file
rs_config.h
rs_context.h	Exposes RealSense context functionality for C compilers
rs_device.h	Exposes RealSense device functionality for C compilers
rs_eth_config.h	Exposes RealSense ethernet configuration functionality for C compilers
rs_frame.h	Exposes RealSense frame functionality for C compilers
rs_internal.h	Exposes RealSense internal functionality for C compilers
rs_option.h	Exposes sensor options functionality for C compilers
rs_pipeline.h	Exposes RealSense processing-block functionality for C compilers
rs_processing.h	Exposes RealSense processing-block functionality for C compilers
rs_record_playback.h	Exposes record and playback functionality for C compilers
rs_safety_sensor.h	Exposes RealSense safety sensor functionality for C compilers
rs_sensor.h	Exposes RealSense sensor functionality for C compilers
rs_types.h	Exposes RealSense structs
hpp
rs_context.hpp
rs_device.hpp
rs_eth_config.hpp
rs_export.hpp
rs_frame.hpp
rs_internal.hpp
rs_options.hpp
rs_pipeline.hpp
rs_processing.hpp
rs_record_playback.hpp
rs_safety_sensor.hpp
rs_sensor.hpp
rs_serializable_device.hpp
rs_types.hpp
rs.h	Exposes librealsense functionality for C compilers
rs.hpp
rs_advanced_mode.h
rs_advanced_mode.hpp
rsutil.h
librealsense2-gl
rs_processing_gl.h	Exposes RealSense processing-block functionality for GPU for C compilers
rs_processing_gl.hpp