By default, the search in Vim editor is case sensitive. But you can also perform case insensitive searches.
Suppose you are searching for the pattern Vim or vim or vIm.
Go to the ESCAPE mode (by pressing ESC key)
Enter :set ic (Note that the semicolon in the beginning is must), ic corresponds to ignore case.
Now enter your search term, /Vim (to search forward) or ?Vim (to search backward).
It will search for all patterns like vim, vIm, vIM, VIM, Vim, VIm,…