Temporarily shifting workloads from private cloud to public cloud during peak demand periods. Like a restaurant opening an outdoor patio when they're too busy to handle customers inside.
An e-commerce site runs on its private servers normally, but automatically bursts to AWS during Black Friday to handle the massive traffic spike.
Cloud bursting is an architecture pattern (hybrid scaling) rather than a single managed service. It’s typically implemented by combining connectivity (VPN/Direct Connect/ExpressRoute/Interconnect/FastConnect), identity, load balancing/DNS, and an autoscaling compute platform (VMs or Kubernetes) so workloads can expand from private infrastructure into a public cloud during spikes.