Interface

Interface is a shared boundary between any two persons and/or systems through which information is communicated.

Definitions

According to the BABOK Guide (3rd edition),

Interface. A shared boundary between any two persons and/or systems through which information is communicated.

According to the INCOSE Systems Engineering Handbook (4th edition),

Interface. A shared boundary between two functional units, defined by functional characteristics, common physical interconnection characteristics, signal characteristics, or other characteristics, as appropriate (ISO 2382‐1).