> If the URL I provide is level 1, and a double click on a 
> link on that page results in a new level, that would be 
> level 2.  What is level 3?
The "level" parameter is the number of "clicks" you can 
make within the mirrored site (external links are treated 
with a different method)

The "clicks" are counted from the **top** index (that is, 
the index page built by httrack, in the project folder)

Level 1 = just get the top level URLs and nothing more (1 
click from the top index)
Level 2 = get the specified URLs and potentially all links 
in these pages (but by default, the engine will limit the 
scope of the mirror to the site and directory structure)
Level 3 = get the specified URLs and potentially all links 
in these pages, and all links in these links
..