Play framework : The template engine

http://www.playframework.com/documentation/2.2.x/JavaTemplates
http://www.playframework.com/documentation/2.2.x/JavaTemplateUseCases
http://www.playframework.com/documentation/2.2.x/ScalaForms
http://www.playframework.com/documentation/2.2.x/ScalaActions

Most of the requests received by a Play application are handled by an Action.
A play.api.mvc.Action is basically a (play.api.mvc.Request => play.api.mvc.Result) function that handles a request and generates a result to be sent to the client.

Put common stuff in main.scala.html, then other (ex. index.scala.html) invoke main to render with different "@content"