Remove[, ... ] removes symbols completely, so that their names are no longer recognized by Mathematica.
Remove["", "", ... ] removes all symbols whose names match any of the string patterns .
You can use Remove to get rid of symbols that you do not need, and which may shadow symbols in contexts later on your context path.
Remove["form"] allows metacharacters such as *, as specified in Section A.3.13.
Remove["context`*"] removes all symbols in a particular context.
Remove does not affect symbols with the attribute Protected.
Once you have removed a symbol, you will never be able to refer to it again, unless you recreate it.
If you have an expression that contains a symbol which you remove, the removed symbol will be printed as Removed["name"], where its name is given in a string.
See The Mathematica Book: Section 1.3.10, Section 2.6.8, Section 2.6.12 and Section A.5.4.
See also: Clear.