SCALABILITY - ability of a system to increase the workload on its current hardware resources ( scale up ); ELASTICITY - ability of a system to increase the workload on its current and additional (dynamically added on demand) hardware resources ( scale out ); Scalability: "Increasing" the capacity to meet the "increasing" workload. Elasticity: "Increasing or reducing" the capacity to meet the "increasing or reducing" workload. Scalability: In a scaling environment, the available resources may exceed to meet the "future demands". Elasticity: In the elastic environment, the available resources match the "current demands" as closely as possible. Scalability: Scalability adapts only to the "workload increase" by "provisioning" the resources in an "incremental" manner. Elasticity: Elasticity adapts to both the "workload increase" as well as "workload decre