Skeuomorphism
Skeuomorphism is a design style that mimics real-world objects and textures in digital interfaces to create familiarity. Examples include buttons that look like physical switches or notepad apps that resemble paper notebooks. The aim is to make digital interfaces feel intuitive by leveraging users’ familiarity with physical objects. While its popularity has waned in favor of flatter designs, skeuomorphism is still effective in certain contexts where realism or usability is paramount.
Skeuomorphism was most valuable during the early smartphone era when users had no existing mental model for touch interfaces — familiar physical metaphors reduced the learning curve dramatically. Today, it's used selectively for interactions that genuinely benefit from physical metaphor: toggle switches that look like physical toggles, turntable controls in music apps, realistic instrument interfaces. The key question is whether the physical metaphor clarifies the interaction or adds unnecessary visual complexity.
GarageBand's instrument interfaces are intentionally skeuomorphic — the piano keys look like piano keys, the drum kit looks like a drum kit. For an app teaching musical instruments, the physical fidelity is a feature, not a limitation, because it leverages users' existing knowledge of real-world instruments.