About http://codex.wordpress.org/WordPress_Feeds

http://codex.wordpress.org/WordPress_Feeds

To be precise, “http://example.com/category/categoryname/feed” has to be “http://example.com/category/categoryname/feed/” and

“http://example.com/tag/tagname/feed” has to be “http://example.com/tag/tagname/feed/”, isn’t it?

I am a beginner, so I may be misunderstanding.
If so, please point it out.