Q. What is interpreter?

An interpreter translates each high-level-language statement into its equivalent set of machine-language instructions, which are then executed right away. Interpretive languages such as Basic are very inefficient for programs with loops (repetitive instructions). The inefficiency is corrected by a compiler,which translates the complete high-level language intomachine language.

Once the whole program is compiled, it can be executed as many times as desired without any need for recompilation. Examples of compiler languages are Fortran, Pascal, and C.

An operating system, such as DOS, VMS, or UNIX, consisting of a set of system programs, performs resource management and human-to-machine translation, supporting a given computer architecture. Operations such as starting and stopping the execution, as well as selecting a specific compiler or assembler for translating a given programintomachine language, are taken care of by the operating system, which is unique for a given microcomputer, minicomputer, or mainframe.