In Bash's Manual, for filename expansion:When a pattern is used for filename expansion, the character . at  the start of a filename or immediately following a slash must be  matched explicitly, unless the shell option dotglob is set. When matching a filename, the slash character must always be matched  explicitly.In other cases, the . character is not treated specially.Can you give some examples to explain the cases in the quote?How shall I distinguish the usage of . in filename expansion from its unrelated usage of hardlink .? 
How shall I understand . in filename expansion?
bash