Meep (or MEEP) is a free finite-difference time-domain (FDTD) simulation software package developed at MIT to model electromagnetic systems. You can download Meep and learn more about it at the Meep home page:
http://ab-initio.mit.edu/meep/
The Meep home page also links to a meep-discuss mailing list for discussions about Meep and FDTD simulations, and a meep-announce mailing list for announcements of Meep releases.
"MEEP" stands for:
MIT Electromagnetic Equation Propagation
or (add your own below):
Maxwell's Equations for Every Person
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