The marks 0-9 are the last 10 files you were editing. See
:h viminfo-file-marks (took me a while to find the correct help subject).
'" : the cursor position when last exiting the current buffer (
:h '"). Exiting here means closing the buffer (
:bd) or exiting Vim while you edit a file. It does not mean leaving the buffer (like switching to another buffer). This mark is stored in the viminfo file (see
:h viminfo). It can be used to restore the cursor position when you edit the file again (see
'^ : the position where the cursor was the last time when Insert mode was
'. : the position where the last change was made (
If you insert some text,
'. will point to the same location (nearly -
'. is on the last inserted char,
'^ after the last inserted char except for end-of-line).
If you do some change without inserting (e.g. delete a line)
'. will reflect that position, while
'^ is unchanged.