Material

1 a (1) : the elements, constituents, or substances of which something is composed or can be made (2) : matter that has qualities which give it individuality and by which it may be categorized <sticky material> <explosive materials> b (1) : something (as data) that may be worked into a more finished form <material for a biography> (2) : something used for or made the object of study <material for the next semester>

2 a : apparatus necessary for doing or making something <writing materials>

Interface

1 : a surface forming a common boundary of two bodies, spaces, or phases <an oil-water interface>

2 a : the place at which independent and often unrelated systems meet and act on or communicate with each other <the man-machine interface> b : the means by which interaction or communication is achieved at an interface