Elastic Load Balancing
An Elastic Load Balancer (ELB) is a virtual appliance that is responsible for distributing traffic to multiple servers so that no single server is overloaded with too much traffic. This ensures the stability of your application and makes it more fault tolerant. If a server gets overloaded, then an Elastic Load Balancer will stop sending traffic to it, allowing it to recover. Since the advent of ELB there have been many versions of it, including, but not limited to an Application Load Balancer, and Network Load Balancer. Each of these different types of load balancers operates on different types of traffic that enter your network so that you as a cloud operator have flexibility and choice when selecting the right load balancer for your applications.
in other words
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