What is the name of the control shown to users with tips, tutorials or other messages usually in a lightbox?

Is there a specific name to the control that is shown to users of web sites/apps that is usually a modal window or lightbox that generally displays content like:

  • Tips
  • Guided walkthroughs
  • Important messages relevant to the user since last time they logged in
  • What's New

Is there a specific name for this control or pattern?

Also, are there recommended libraries to implement this control/experience in a web application?

Here's an example from the web site for AppDynamics: example whats new lightbox from AppDynamics