"Cloud computing is a new way of delivering computing resources to run websites and web applications. Cloud computing allows customers to take advantage of a self-service, pay-as-you-go utility model that ensures they are only running (and paying for) as much computing capacity as they need. Think home utilities, such as water and electricity.
"Cloud computing allows customers to scale vertically and horizontally, and based on the demands of their users, it ensures there are enough resources at any given time. If a traffic spike occurs, it’s easy to add more capacity. After the traffic trails off, it’s just as easy to reduce capacity. And if additional components are added, you simply adjust capacity as needed.
"Ultimately, a customer’s cloud computing resources can grow, shrink, or morph based on the changing demands of their business. This significantly reduces the costs of running websites and web applications, often eliminating capital expenditures and lowering operating costs.
"One important thing to note about cloud computing is that while it offers obvious cost savings by helping companies offload the task of racking and stacking hardware, it also requires a new set of software development expertise in terms of enabling applications to run in the cloud. This is what Engine Yard and other cloud providers do: We provide a platform-as-a-service that allows applications to leverage cloud computing capacity."