Because I always find it difficult to explain to someone what I do, I found this picture to be a very good starting point of a conversation about the topic.
UX approach to solving design problems is one that goes top down from conceptual ideas (UX Strategy) to very specific design solutions (Interaction Design), in that sense our field needs powerfull memes like this one to help evangelize the field.

On the other hand when one is very much involved with IT development teams (like me for the past months) and the discussion is between “out of the box solutions” versus custom development, this image also helps explain the idea to developers and business.

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