Introduction: The Invisible Interference
Modern Wi-Fi can easily reach gigabit speeds, making it faster than many cheap Ethernet cables. So why do professional gamers refuse to use Wi-Fi? The answer isn't speed (bandwidth); the answer is Latency (Ping).
The Carrier-Sense Wait
Wi-Fi operates on shared airwaves. If your laptop wants to send an IP packet, it must 'listen' to see if a neighbor's router or a microwave is using that frequency. If the air is busy, it waits a few milliseconds. This happens constantly, creating tiny, unpredictable 'Jitters' in your ping. An Ethernet cable is a closed environment. The copper wire belongs entirely to your computer, meaning the data travels instantly with zero waiting time.
Conclusion
For large downloads, Wi-Fi is perfect. For real-time, millisecond-perfect inputs (like gaming and stock trading), nothing beats the stability of a physical cable. Test your jitter score here.