A work that is not “fixed” is not protected; this might include such works as improvised speeches or songs that have neither been written out in advance, nor recorded during performance. An unpublished letter or diary is “fixed” and therefore copyrighted. Ideas cannot be copyrighted until fixed in a tangible form. And “works consisting entirely of information that is common property and containing no original authorship” cannot be copyrighted-this includes items like calendars, tables of weights and measures, etc. (Copyright Basics 4-5).