An autoresponder is software that automatically delivers to an e-list a series of e-mail messages, which you write, according to a schedule you specify. Delivery of the series is typically triggered by e-mail address capture.

The most popular autoresponder is Aweber. The shopping cart software Web Marketing Magic also has a built-in autoresponder.

The use of autoresponder e-mail series is limited only by your imagination, but here are the 5 most common applications.

1-Online conversion - in online conversion, a series of e-mails is sent to a visitor who requested your free content but did not buy a product, in an attempt to get him to reconsider his decision and place an order.

2-Cross selling - when a customer orders a product, the autoresponder serves him a series of e-mail messages attempting to sell him another product that might be of interest, usually related to or complimentary to the first product.

3-Up sell - similar to cross-selling except you are trying to sell the customer a product at a higher price point than the one he purchased; if the initial purchase was an e-book on Topic X for $39, the up-sell e-mails might offer an audio album on Topic X at $97.

4-Consumption - a series of e-mails that explains how to use the product and encourages the buyer to do so; the logic is that a buyer who uses your product is more likely to buy more products from you and less likely to return the first product.

5-Maintenance - for membership web sites, subscription newsletters, and products sold with monthly payment schedules, a series of e-mails is sent to encourage the customer to stick with the product and not drop out or cancel.