On Tuesday, Facebook is expected to unveil changes to PHP, the language that helped make the social networking site a success - along with millions of other web sites. SD Times has outed the planned change here. Facebook wouldn't provide details when contacted by The Reg but said it would make more details available Tuesday morning, Pacific time. The changes have been described as either a re-write of the PHP runtime or a compiler for PHP. A change to PHP would be Facebook's latest donation to the language, which has also had contributions from Microsoft and the former Sun Microsystems over the years.