What is the pricing model that allows AWS customers to pay for resources on an as-needed basis?

The pricing model that allows AWS customers to pay for resources on an as-needed basis is known as "Pay as you go." This model enables users to only incur costs for the services and resources they actually use during a specific period of time, without the need for long-term commitments or upfront payments. This flexibility is particularly advantageous for businesses with variable workloads, as it allows them to scale resources up or down based on current needs without being locked into fixed costs.

This approach stands in contrast to other models, such as reserving resources ahead of time or similar concepts, which could require upfront payments or commitments to a certain usage level. "Pay as you go" promotes cost efficiency and resource optimization, making it a key feature of AWS's pricing strategy that appeals to a wide range of customers from startups to large enterprises.