How does an icon resemble the thing it represents?

In the study of semantics and semiotics, an icon is defined as a sign that denotes its object through an extra-systemic resemblance. Unlike other types of signs that may rely on convention or abstract association, an icon represents the thing it denotes by sharing specific external qualities or appearances with that object.12

This resemblance is typically visual or structural, allowing the icon to function as a likeness, image, or depiction of the person or thing it represents. For example, a two-dimensional design, such as a picture or illustration, acts as an icon because its physical form corresponds to the appearance of the subject it portrays. In this context, the icon does not merely point to an object; it mirrors its characteristics, creating a direct, observable connection between the sign and its referent.3421