This inheritance list is sorted roughly, but not completely, alphabetically:

CApplication	Test application
CCore::CR< id >	Access to the Control Register
CIOPort	Abstracts access to the I/O address space
CKeyboardApplication	Keyboard Application
CKeyDecoder	Decoder for keyboard codes received from the PS2Controller
CMultiboot::Memory	Memory Map
CMultiboot::Module	Boot Module (also known as initrd = initial Ramdisk)
CCore::MSR< id >	Access to the Model-Specific Register (MSR)
CNullStream	Ignore all data passed by the stream operator
CSerial	Serial interface
CSerialStream	Console (VT100 compatible) via Serial interface
CStringbuffer	The class Stringbuffer composes single characters into a longer text that can be processed on block
COutputStream	The class OutputStream corresponds, essentially, to the class ostream from the C++ IO-Stream library
CConsoleOut	Write text on console (STDOUT)
CCopyStream	Duplicate all data passed by the stream operator to two output streams
CFileOut	Write text into file
CSerialStream	Console (VT100 compatible) via Serial interface
CTextStream	Output text (form different data type sources) on screen in text mode
CTextMode	Basic operations in the VGA-compatible text mode
CTextWindow	Virtual windows in text mode
CTextStream	Output text (form different data type sources) on screen in text mode