Elastic Load Balancing
Elastic Load Balancing lets you automatically distribute the incoming traffic (or load) among all the instances you are running. The service also makes it easy to add new instances when you need to increase the capacity of your web site application.
Customers reach your web site via your web URL, such as www.mywebsite.com. This single address might actually represent several instances of your running web application. To always have an available web site, you need to run multiple instances. Otherwise, your customers might see delays when accessing your site, or worse, might not be able to access your site at all.
Elastic Load Balancing manages the incoming requests by optimally routing traffic so that no one instance is overwhelmed. You can quickly add more instances to applications that are experiencing an upsurge in traffic or remove capacity when traffic is slow.
For more information, refer to the Elastic Load Balancing Developer Guide.