usb_cam rosmake failed. [closed]

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asus@asus-K46CB:~$ cd //home/asus/Desktop/ROS/usb_cam/ asus@asus-K46CB://home/asus/Desktop/ROS/usb_cam$ rosmake

[ rosmake ] rosmake starting...
[ rosmake ] No package or stack specified. And current directory 'usb_cam' is not a package name or stack name. [ rosmake ] Packages requested are: []
[ rosmake ] Logging to directory /home/asus/.ros/rosmake/rosmake_output-20151220-040002 [ rosmake ] Expanded args [] to: []
[ rosmake ] ERROR: No arguments could be parsed into valid package or stack names. asus@asus-K46CB://home/asus/Desktop/ROS/usb_cam$

i check nano .bashrc faile patch way. it is true . and i cant rosmake usb_cam patch. can u help me about that.

actually i am new on ROS . can u help me? i am beginner . i need make simulation in HECTOR SLAM. thanks.