The isn't talking about that sort of "interface" (which Ada also has). This refers to a difference in logical and physical program structure in which specifica

The isn't talking about that sort of "interface" (which Ada also has). This refers to a difference in logical and physical program structure in which specifications are separate from bodies--formalized version of the header/source separation in C/C++. In addition to logical separation, this provides speed ups in recompilation times.