Coding concept used with various programming languages:

""a reference provides another name for a variable. whatever you do to a reference is done to the variable to which it refers You can think of a reference as a nickname for a variable." Beginning C++ Game Programming
http://books.google.com/books?id=hZJXjztv6wIC&pg=PA161

http://www.java2s.com/Tutorial/Cpp/0140__Function/Passingref...

http://www.justskins.com/forums/passing-references-57563.htm...

""There are two types of references in programming: reference to a common point on the part.... reference to a previous point on the part""
CNC Programming Handbook, http://books.google.com/books?id=JNnQ8r5merMC&pg=PA348