What do we call the relationship between something (the design) and another thing (the reference)

Sorry for the poorly written title, cannot think of how to write it better. I am looking for a word or phrase that roughly means "metaphorical environment". I'll explain:

The email system and protocols are designed based on the traditional snail mail system. For example the inbox works like a letter box where incoming mails reside. Then you may retrieve the mail from the letter box and sort them into folders at home, which you can similarly do on the email system. When you write a physical letter, you need to post it out, to somewhere, and we have the outbox for the same in an email system.

I want to express that the email system borrows ideas from traditional mail and is a "metaphorical environment", so if we think about the traditional mail system, we can better understand how email system works.

How can I express this in a proper sentence? Can I just say, "the email system is a metaphor of the traditional mail system"?

Solution 1:

So there are a number of terms that might be useful/relevant here. Many of these are from Donald Norman's Design of Everyday Things (an excellent book).

First is the idea of the conceptual model, which is how a particular object/interface is understood. There are 3 relevant terms:

• The design model is the designer's conceptual model.
• The user's model is the mental model developed through interaction with the system.
• The system image results from the physical structure that has been built (including documentation, instruction, and labels).

Going back to your original example, relating email to snail-mail provides a mental model for understanding the former. Specifically, this is a natural mapping, which takes “advantage of physical analogies and cultural standards, lead[ing] to immediate understanding”.

Another somewhat related concept is that of a skeuomorph:

A skeuomorph is a derivative object that retains nonfunctional ornamental design cues (attributes) from structures that were inherent to the original. Examples include...a software calendar that imitates the appearance of binding on a paper desk calendar.

Skeuomorth doesn't directly relate to the mapping between snail-mail and email, since the connection is more than superficial. However, design elements like using an envelope icon for the Send button could be considered skeuomorphs to strengthen the mapping.