git commit -a confusion

Question

I am using Git Bash and am trying to figure out what is happening when I type \'git commit -a\'.

Looks like VIM opens up to edit my commit message but how do I save

Answer 1

this is a question about VIM and not git itself (if i'm not mistaken)

VIM uses multiple modes, to exit insert mode hit ESC or ^C. to save and exit the file use ZZ, :x or :wq

just to be complete: git commit -a will first add all tracked and changed files' contents to the index and then creates a commit (after specifying the commit message inside vim – or your editor of choice)