Any conversation about cloud computing will eventually lead to the question "Why? What's the benefit and why should I be using cloud computing?" There are multiple factors that contribute to cloud computing outperforming the traditional, on-premises data center-oriented approach to computing, but the following capabilities are the ones that are the most likely to make on-premises data centers a thing of the past:

• The ability to trade capital expenses for operational expenses when running IT
• The ability to use inexpensive compute units on demand
• Increased application delivery speed and agility
• Capacity matched to demand
• The ability to go global in minutes

Perhaps the most prominent advantage when using Amazon Web Services is the ability to deploy your services globally within minutes. Using scripts, templates or 3rd party tools, you can deploy your application to any region where AWS operates with simplicity and great velocity. AWS also offers its customers the ability to very simply synchronize their data across regions and deliver an application to a broad range of audiences with the lowest possible latency.

Secondly, the ability to trade in capital expenditures for operating expenditures is very important. AWS allows users to provision and consume resources on demand, whenever resources are needed, and to scale those resources dynamically. There is complete control from the user's end regarding when and how to use the platform, the services, and resources provided, and the user also has complete control over the way they pay for that consumption, giving them the ability to pay only for the exact amount of usage in the cloud. This is a very valuable proposition to any business, as the cost of computing and application delivery can be relative to the demand for the application, and thus the income the business receives from providing the application for its users.

There is also the ability to use very inexpensive units of computing compared to traditional data centers and compared to the on-demand cloud services on offer. AWS allows its customers to essentially bid on unused resources that are reserved to provide other customers with dynamically expandable capacity. The users bidding on the unused capacity have the ability to use the capacity they bid on until any other client bidding a higher price or paying the regular on-demand price requests that capacity. As a price bid jumps to a higher price or the on-demand price, the lower bidder is outbid and their resources are terminated in favor of the higher bidder. We will discuss the way this feature operates by looking at the Elastic Cloud Compute (EC2) spot instance marketplace in a later chapter.

Lastly, the ability to increase application delivery velocity and agility should not be overlooked. By utilizing a combination of DevOps approaches, agile methodologies, and using PaaS, any application development company can tune the performance of their development teams to deliver their applications in an increasingly fast manner. This allows them to quickly react to any new business requirements, changing market conditions, and other factors outside the business itself.