For questions on interfacing or getting Mathematica to work together with other software or technologies. If your question is about a specific language you want to interface with Mathematica, please consider using the appropriate *link tag.
Built in interoperability interfaces:
WRI and third party interoperability packages and interfaces:
Pythonika for calling Python from Mathematica
SystemFiles/Links/Pythonsubdirectory of the Mathematica installation for calling Mathematica from Python
SystemFiles/Linksdirectory contains several packages for interfacing Mathematica with various technologies (some of these packages are unsupported).