These conversion programs turn the programmer's source code, which is what the programmer writes, into machine language (machine code). See assembly language, compiler and interpreter.

See compiler. Assembly Language vs. Machine Language Although the terms are often used synonymously, assembly language and machine language are not the same.

Actually, the code reads a simple language, uses recursive descent parsing to build a tree, and then uses a “compiler” to convert the tree to JavaScript (which can then be executed, of course).