Shutting down an ARMLinux machine is substantially different from what you are used to. Simply resetting the machine can for example lead to the corruption of data, or at least a very slow boot due to the disc-checking process. You can shut the system down properly with the halt command although you will have to be logged in as root:
If you want to reboot then you use reboot instead. Even easier is to use Ctrl-Alt-Del which also does 'reboot', even if you are not root. These are actually synonyms for various options to the shutdown command - ie shutdown -h now is the same as the halt command. There are of course many other options or switches that you can use in relation to this command, but you don't need to know those now. Use man 8 shutdown to read the details if you are interested.