What is a universal binary application?

A universal binary application refers to software that is designed to run natively on both PowerPC and Intel-based Macs. This means that the application contains multiple sets of executable code, allowing it to optimize performance depending on the hardware architecture of the system it is running on. This approach was introduced by Apple to ensure compatibility during the transition from PowerPC processors to Intel processors, allowing users with either architecture to run the same application without issues.

The other options do not accurately describe a universal binary application. For instance, software designed solely for Intel-based Macs would not support users with PowerPC systems, making it non-universal. Multimedia software for video conferencing does not particularly address the multi-architecture capability of universal binaries. Lastly, a program that operates only with external hardware is unrelated to the concept of universal binaries, which focuses on software compatibility across different processor types.