Board Thread:General Discussion/@comment-22224-20180521161500/@comment-24155515-20180613153932

Monobook was introduced in August 2004. It's internet-old, but it's not 98 old (though 98 computers were still in use in '04, I suppose). It's not even as old (2001) as Wikipedia. (Before Monobook was introduced, a skin called Standard (aka Classic) was used.)