a high-level programming language that is translated into machine code line by line as it is executed. BASIC and LISP are interpreted languages. The chief advantage of an interpreted language is rapid alteration of the program, the penalty for which is slow execution.
a programming language that is compiled into machine readable code at the moment it is run by the languages interpreter
A language that is changed from source code to machine language in real-time. Examples of this are BASIC (the PC version, and the Ti-version), JavaScript, HTML (bad example…but you get the point). The advantages are interpreted languages are often much simpler, good for beginners. Bad points are speed, and no native is generated.