The difference is that elastic load balancers are the things that actually implement the redundancy in AWS, and if one goes down and another can't be immediatel

The difference is that elastic load balancers are the things that actually implement the redundancy in AWS, and if one goes down and another can't be immediately started in it's place, no traffic will be getting to the instances that sit behind it. I believe AWS has been working on a solution to this, but thus far haven't released anything.