Sorry for being rude, I should think twice before posting.

$ indicates user's command prompt so it should not be typed. Anything that comes after it is the command. With --help flag most commands will show a help page, which will tell you the syntax to use and some useful command line arguments (aka flags). For example:
Its output will tell us among other things that -T flag will run movgrab in test mode and show available video formats and resolutions without actually downloading anything.

If you just want to download a file, without specifying a resolution or a format you can just type movgrab followed with an URL to a web page showing the video. For example:
Movgrab works also for many other sites.