When you have a lot of data and a lot of computation to be performed, you might start to crave more computing power. Amazon (http://aws.amazon.com) allows you to rent computing power by the hour. Thus, you can access a large amount of computing power without having to precommit by purchasing a large number of machines (including the costs of managing the infrastructure). There are other competitors in this market, but Amazon is the largest player, so we briefly cover it here.
Amazon Web Services (AWS) is a large set of services. We will focus only on the Elastic Compute Cloud (EC2) service. This service offers you virtual machines and disk space, which can be allocated and deallocated quickly.
There are three modes of use. First is a reserved mode, whereby you prepay to have cheaper per-hour access, a fixed per-hour rate, and a variable rate, which depends on the overall compute market (when there is less demand, the costs are lower; when there is more demand, the...