Once a problem has been examined, and the algorithm for its answer has been refined and written, the algorithm then is translated into the specific programming language. The computer program is a series of instructions, in a given language, which completes a task. To execute or run a program is to have the computer actually follow these instructions.
The High-level languages have English-like commands and functions, like "print this" or "if x < 5 then do something." The computer can, though, understand commands only written in its machine language. The programs which are written in high level languages should therefore be translated into machine language before the computer can actually execute the series of instructions in the program. A program which does this translation from a high-level language to an executable file is termed as a compiler. The original program is known as the source code, and resulting executable program is known as the object code.
By the contrast, an interpreter goes through the code line-by-line, executing each command as it goes. The MATLAB uses either what are termed as script files or M-files (the motive for this is that the extension on the filename is .m). These scripts files are interpreted, instead of compiled. And hence, the correct terminology is that these are the scripts, and not programs. Though, the terms are somewhat loosely used by many people, and documentation in the MATLAB itself refers to the scripts as programs.