Open closed principle

Question

Hello please explain this idea.I got this from Martin book.

They are closed for modification. Extending the behavior of a module does not result in changes

to the source, or binary, code of the module. The binary executable version of the

modulewhether in a linkable library, a DLL, or a .EXE fileremains untouched.

thanks in advance

Answer 1

http://www.devx.com/dotnet/Article/6997/0/page/1

Answer 2

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vbcon/html/vbconinternationalizingapplications.asp

Answer 3

http://www.microsoft.com/globaldev/

Answer 4

https://www.aspsnippets.com/Articles/ASPNet-Multilingual-website-Support-and-display-Multiple-Languages-English-French-in-ASPNet.aspx