Serverless
Serverless is the cloud-computing model in which the cloud provider runs and scales the underlying infrastructure transparently, the developer deploys code (functions, containers) and the provider handles servers, capacity, and most operational concerns. Pricing is usage-based (per request, per GB-second) rather than per provisioned instance.
Serverless covers a spectrum: FaaS (Lambda, Cloud Functions) is the strict definition; managed databases (DynamoDB, Aurora Serverless), managed queues, and edge runtimes are commonly grouped under the same umbrella. The economic model favours bursty or low-traffic workloads where the per-request cost beats the provisioned-instance cost; high-throughput steady-state workloads usually cost more on serverless than on right-sized provisioned instances. Other trade-offs: cold-start latency, vendor lock-in (most serverless code is provider-specific), and observability/debugging that's harder than for traditional servers. The strongest fit is event-driven async work, webhook handlers, scheduled jobs, fan-out processors.