+If you want build a platform, ACTIVE_PLATFORM must be set to your desired\r
+platform dsc file, go to directory which must be not a module's directory, and\r
+run "build" command.\r
+\r
+Instead of changing Target.txt, you can specify platform, module and/or\r
+architecture on command line.\r
+For example, if you want to build NT32 platform, you can just type \r
+\r
+ c:\MyWork\edk2\> build -p Nt32Pkg\Nt32Pkg.dsc -a IA32\r
+\r
+and if you want to build HelloWorld module, you can just type\r
+\r
+ c:\MyWork\edk2\> build -p Nt32Pkg\Nt32Pkg.dsc -a IA32 -m MdeModulePkg\Application\HelloWorld\HelloWorld.inf\r
+\r
+Other helpful command line options of build tool include "-v" and "-d".\r
+The "-v" option is used to turn on the verbose build, which provide more\r
+information during the build. "-d <debug level 0-9>" option is used to\r
+turn on the debug information which is helpful debugging build tools.\r
+\r
+For more information on build options, please try "build -h" on command line.\r
+\r
+Note:\r
+ The Windows style help option "/?" is not a valid option for the build\r
+ command.\r
+\r
+\r
+-------------------------------------------------------------------------------\r
+Supported build targets\r
+-----------------------\r
+\r
+all - Build whole platform or module. It can be ignored.\r
+genc - Generate AutoGen.c, AutoGen.h and <ModuleName>.depex files only.\r
+genmake - Generate makefiles in addition to files generated by "genc" target.\r
+clean - Clean intermediate files\r
+cleanall - Clean all generated files and directories during build, except the\r
+ generated Makefile files (top level and module makefiles)\r
+cleanlib - Clean all generated files and directories during library build\r
+run - Launch NT32 shell (only valid for NT32 platform)\r