interface wiki:
eneral usage, an interface is the point, area, or surface along which two substances or other qualitatively different things meet; it is also used metaphorically for the juncture between items. The word interface is sometimes (usually in technical disciplines) shortened to "i/f". The verb to interface means to interconnect two or more entities at a common point or shared boundary, or to prepare either entity for that purpose.
See more at Wikipedia.org...
design wiki:
ly considered in the context of the applied arts, engineering, architecture, and other such creative endeavours, "design" is used as both a noun and a verb. "Design" as a verb refers to the process of originating and developing a plan for a new object (machine, building, product, etc.). As a noun, "design" is used both for the final plan or proposal (a drawing, model, or other description), or the result of implementing that plan or proposal (the object produced).
See more at Wikipedia.org...