USB vs. IEEE 1394 (FireWire): what is the most significant difference between the standards in classic PC contexts?

Introduction / Context:
Legacy PC interfaces offered two popular serial buses: USB (notably USB 1.1 at 12 Mb/s at the time) and IEEE 1394 FireWire (commonly 400 Mb/s, later 800 Mb/s). Understanding their comparative speed and features informs device selection for storage, video capture, and audio interfaces.

Given Data / Assumptions:

• Comparison refers to the classic era: USB 1.1 vs IEEE 1394a (FireWire 400).
• Typical peripherals: scanners, cameras, external drives.
• Both buses support hot plugging in their standard implementations.

Concept / Approach:
In that historical context, IEEE 1394 was significantly faster (up to 400 Mb/s, later 800 Mb/s) and provided isochronous transfer modes useful for real-time audio/video. USB 1.1 topped out at 12 Mb/s. Both were plug-and-play and hot-swappable in mainstream OS support, so speed was the most striking difference then.

Step-by-Step Solution:

Verification / Alternative check:
Benchmarks of external HDDs and DV camcorders from that era consistently favored IEEE 1394 for sustained transfers.

Why Other Options Are Wrong:

• USB does not support USB: Nonsensical.
• USB is plug and play: True but not unique; IEEE 1394 is also plug and play.
• IEEE 1394 is hot swappable: True but USB is hot swappable too; not the distinguishing factor.

Common Pitfalls:
Comparing later USB 2.0/3.x speeds retroactively; the question frames a classic comparison where FireWire was faster.

Final Answer:
IEEE 1394 is faster