(Since now there is a wiki page entitled Modes.MathematicaMode although such a mode does not exist in Alpha, I guess there should be a page for the Maple mode -- which has the merit of existing.)
Maple is one of the leading multi-purpose programmes for symbolic and numerical computation in mathematics. The front page for Maple is http://www.maplesoft.com/
Maple is commercial closed-source software.
Alpha sports a Maple mode for editing maple source code. The features of Maple mode are keyword colouring, auto indentation, some electric template insertions, file marking, and fancy navigation.
There is currently no support for interaction with maple. Maple is not really designed to be driven by another application: its batchmode will only accept filenames as input, so you need to do tricks with /bin/sh and here-documents... and it is also quite slow at starting up. And if you try to run maple through a pipe you face an annoying problem with the prompts: they are never sent when they should be, because maple doesn't flush its output channel when it should, so the prompts always come together with the following input-echoing...