step-1 update intro

diff --git a/examples/step-1/doc/intro.dox b/examples/step-1/doc/intro.dox
index a077750b4ad2b8e1f301897092421dab11745588..d0393e4b20a6bbd281b72c968902825574b03df7 100644 (file)
--- a/examples/step-1/doc/intro.dox
+++ b/examples/step-1/doc/intro.dox
@@ -128,6 +128,11 @@ command line, you may be interested in watching lectures 2.9 and 2.91.
 (@dealiiVideoLectureSeeAlso{2.9,2.91}) These give overviews over the command
 line and on what happens when compiling programs, respectively.
 
+Note that deal.II is actively developed, some functions were renamed
+after video lectures were ready. For example, step-1 code shown in the
+video lecture 5 has a class HyperShellBoundary which was replaced with
+SphericalManifold class later on. However, in spite of such kind of
+details the content of the lectures is still very relevant.
 
 <h3> What this program does </h3>
 
@@ -152,6 +157,7 @@ of introduction.
 @dealiiVideoLecture{5,6}
 
 
+
 <h3> About scientific computing in general </h3>
 
 If you are reading through this tutorial program, chances are that you are