"Free and clear" means free of any debt, liens and encumberances. If you buy at a foreclosure auction you may inherit liens that are attached to the property, so it will not be "free and clear". A proper foreclosure procedure by the bank is supposed to wipe out all liens attached to the property so it can become "free and clear".
In order to make sure your foreclosed home in Fort Lauderdale is free and clear, you may want to hire a title company to perform a search for liens and encumbrances. Foreclosures are well known for having tax liens attached to them, or mechanic's liens from contractors, or even permits for work that was performed but that were never closed out.
If you don't check on these items beforehand, you may find yourself with a seemingly great deal that is full of unplesant economic suprises that will bite you in the wallet.