This is an update of the Villanova catalog published in the ApJS paper, corresponding to the Web version of the catalog in August 2006 (see http://www.astronomy.villanova.edu/WDCatalog/index.html). The introduction to the 1999 catalog is in the file "preface.tex". This version includes many additions and corrections to the original 4th edition: additional entries (555 newly discovered white dwarfs), additional data for previously known white dwarfs (marked in the catalog); new SDSS photometry has also been added. The total number of white dwarfs in this version is 5557.