Grunt is a Task Runner which is used to automate the process in the java script. To run a grunt command type grunt taskname in the cmd.

Syntax to Run a Task : grunt Taskname.

Example

//Tasks:
          grunt.loadNpmTasks('grunt-bower-concat');
          grunt.loadNpmTasks('grunt-bower-install');
          grunt.registerTask('builddev', 
          ['clean:dev','bower_concat:dev', 'concat:devlibcss', 'copy:dev', 'watch:dev']);
          grunt.loadNpmTasks('grunt-contrib-uglify');
          grunt.loadNpmTasks('grunt-stripcomments');
          grunt.loadNpmTasks('grunt-htmlclean')

The above example is the tasks for the grunt. This will automatically run the tasks when required.