Elasticity in cloud computing refers to the system’s ability to adapt to workload changes by provisioning and de-provisioning resources in an autonomic manner, enabling businesses to scale up or down based on demand. This is crucial as it allows for cost efficiency; companies only pay for what they use. It also ensures high availability and performance because during peak times, additional resources can be allocated to handle the increased load, preventing system overloads or crashes. Furthermore, elasticity supports business growth without requiring significant upfront investment in infrastructure.