More than one will.

If you revoke your Will, it is legally dead - as if you never created it.  You can revoke your Will by a later writing a new Will or "codicil" (an amendment to a Will) that is totally inconsistent with your previous Will or that includes a statement that you intend to revoke your previous Will.  When makig such a statemnt it is usually sufficient to say something to effect that you "hereby revoke all prior Wills and codicils”.  You can also revoke a Will by physically destroying it (burning, canceling, tearing, or obliterating it).  If you physically destroy your Will, make sure you destroy the entire Will; otherwise you risk an ineffective revocation.  For example, if you want to write "void" on your Will, write it across the face of every page, not just the first page. Frankly, doing all of the above is a good idea - that is, have a statement in your new Will revoking all previous Wills and physically destroy or write "void" on your previous Will.