APL: everything is a matrix
LISP: everything is a list
Xanadu: everything is a fat pointer to constant or append-only data
SQL: everything is a row
Forth: everything is a word
UNIX: everything is an FD (except ioctl, network sockets, shell procedures…)
C: everything is a mutable unbounded byte array (except preprocessor macros)
Smalltalk: everything is an object
PROLOG: everything is a predicate (except atoms and lists)
Objective C and C++: everything is an object (except the things that already existed in C)
Plan9: everything is a file (no, really)
Java: everything is an object (except primitive types and methods and…)
AJAX/DHTML: everything is a DOM node