MMP - Symbian Project Specification File
This is a file type used by the Symbian OS as a part of their development tools. It contains project properties that are used to compile the project regardless of the compiler or platform being used. It's also part of the Symbian software development kit's makmake or abld tools which converts the file into a makefile for specific platforms. MMP files can also contain references to source code files, and targets to be compiled and can also include directories and other application resources.