What should I look for in ftp?

A key usage of Expect involves commercial software products. Many of these products provide some type of command-line interface, but these usually lack the power needed to write scripts. They were built to service the users administering the product, but the company often doesn't spend the resources to implement a fully robust scripting language. An Expect script can spawn a shell, look up environmental variables, perform some Unix commands to retrieve more information, and then enter into the product's command-line interface armed with the necessary information to achieve the user's goal. After looking up information inside the product's command-line interface, the script can make an intelligent decision about what action to take, if any.