Describe the term "failover" in network switching.

Failover in network switching refers to the process of seamlessly transitioning to a backup system or component when the primary one experiences a failure. This is crucial in maintaining network availability and reliability, as it ensures that users and applications can continue to function without noticeable interruption. For instance, if a primary switch or link goes down, the network can quickly reroute traffic to a secondary switch or backup connection, preserving service continuity. This mechanism is essential for critical systems that require high uptime, such as in data centers or enterprise networks, where downtime can lead to significant operational challenges and financial impacts.

The other options represent different concepts unrelated to the specific definition of failover. Upgrading network hardware, balancing load, and performing routine maintenance are all important activities in network management but do not convey the essence of failover, which focuses on redundancy and system resilience in the face of failure.