What's the difference between AutoPlay and autorun?

AutoPlay

AutoPlay is a Windows feature that lets you choose which program to use to start different kinds of media, such as music CDs, or CDs or DVDs containing photos. For example, the first time you try to play a music CD, AutoPlay asks which media player you want to use, if you have more than one installed on your computer. You can change AutoPlay settings for each media type.

Autorun

Autorun is a technology used to start some programs or enhanced content (such as video content on a music CD) automatically when you insert a CD or another media type into your computer. This is different from AutoPlay, but the result is often the same: when inserted, the CD starts automatically, using a particular program. Autorun is incorporated into the media types that use it, and you can't modify it.

When you try to play a CD or another media type that uses autorun, AutoPlay asks you to choose an action to perform (for example, to play the autorun content or to skip it).