At its core, an air gapped system is a network or computer that is physically isolated from unsecured networks, such as the internet or non-secured local networks. This isolation eliminates the possibility of remote cyberattacks through traditional network-based vectors, making it an effective countermeasure for high-value assets.

A Historical Perspective
The air gap concept is hardly new, having its roots in the early days of computing. Initially, it was a natural byproduct of standalone computer systems and later a deliberate strategy for securing sensitive data. Over time, its prevalence has grown, largely in response to the sophistication of cyber threats.