Understanding lvalues and rvalues in C and C++

lvalue: locator value represents an object that occupies some identifiable location in memory

i.e. has an address

an rvalue is an expression that does not represent an object occupying some identifiable location in memory.

http://eli.thegreenplace.net/2011/12/15/understanding-lvalues-and-rvalues-in-c-and-c/

Conversions between lvalues and rvalues

All lvalues that aren’t arrays, functions or of incomplete types can be converted thus to rvalues.