What does 'm' mean in this cmake file?

Hi,

I am learning cmake for cross compiling ARM projects. The following is from an on-line cmake tutorial. I do not understand what the 'm' means on the fifth line. Could you tell me that?

Thanks,

............................. include_directories(${CMAKEDEMO_SOURCE_DIR}/w01-cpp) link_directories(${CMAKEDEMO_BINARY_DIR}/w01-cpp)

#the one C file add_executable(cdemo cdemo.c) target_link_libraries(cdemo m) #link the math library

#these are all compiled the same way set(PROGRAMS oglfirst pointers) set(CORELIBS ${GLUT_LIBRARY} ${OPENGL_LIBRARY} m)

foreach(program ${PROGRAMS}) add_executable(${program} ${program}.cpp) target_link_libraries(${program} ${CORELIBS}) endforeach(program)

#building just a library. add_library(geometry geometry.cpp)

add_executable(test_geometry test_geometry.cpp) #linking against a custom library target_link_libraries(test_geometry ${CORELIBS} geometry)