The Dock is often described as "like the taskbar". As little as I like the Dock, that is far from an accurate description, and absolutely no offense to
Francine!
As with most MS 'features' the Task Bar, AFAIK, has mainly two modes: Hidden or Visible. It's always at the bottom, always the same size, always has most of the same stuff in it, basically text only, etc. Take a look at some of Apple's demos and you'll get a better idea of what the Dock can do and how it can be used, placed, sized, etc. The Dock is like the Task Bar like OS X is like Windows/Vista!
Well, they
both use the screen!
On the other hand, you can sometimes get a window back ( possibly without the mouse ) if the program keeps track of its windows
and assigns a keyboard shortcut to them ( command-1, command-2, etc. ). I'm trying to remember how to navigate menus with the keyboard.
And that may only work in Finder. Anyway, command-tab will bring up the list of currently running apps, tabbing will scroll through the list, then one can hopefully select the programs "Windows" menu and select the one you want ( even if it's hidden/in the Dock ).
Of course, it's a lot simpler to simply click the windows icon!