M file extension

Mathematica (software that is used to generate and run mathematical functions) file with functions or a set of instructions which is stored using a text format that may be opened and edited using any text editor. The "init.m" file stores initialization properties which are loaded when the program starts.

MATLAB (software that is used for mathematical computations) text file with a script, class or an individual function stored using the MATLAB language. It is used to execute algorithms, plotting graphs and perform other mathematical operations. This file is also called an "M-File".

Created with the Mercury functional programming language (created at the University of Melbourne) source code file which uses a plain text format and syntax that is similar to the Prolog language. Mercury was created for providing a robust language for large real world programs. It contains various error-checking functions which are not provided by other logic programming languages. The developmental edition of the Mercury compiler is provided in a source code format and does not contain compiler binaries. Windows port of Mercury (winmercury) contains binaries and Vim syntax highlighting files for source code editing.

Applications created using Objective-C class implementation file that starts with the @implementation directive and initializes variables and functions which may be referenced by other Objective-C source files. It can also reference header (H) files. Objective-C is usually used for implementing programs for Apple Mac OS X and iOS systems. Apple Cocoa API and iOS API provide the Objective-C programming interfaces for these platforms.