csquotes

[Wolfgang Engelmann]

I get this warning

Package biblatex Warning: 'babel/polyglossia' detected but 'csquotes' 
missing.

(biblatex) Loading 'csquotes' recommended.

and the pdf output does not work.

I checked in the net and there are discussions on enquotes and csquotes, 
but I do not understand it.

Can somebody help?

Wolfgang