You can use an autoresponder for many different tasks. Here are just a few examples of how an autoresponder can be used.
1. Deliver a course over time to subscribers.
2. Deliver a series of links to blog posts.
3. Deliver a series of reminders about a new product.
4. Deliver a series of messages with links to funny articles or videos.
5. Deliver messages with different links to different articles in a series every few days.
I could go on and on. But, just use your imagination and come up with ways you could use an autoresponder to inform and communicate with your subscribers.