Set the mark

m{a-zA-Z}

marks the current cursor location with the designated letter. lowercase marks are local to each individual buffer. uppercase marks are globally accessible.

Two Normal mode commands

'{mark}

moves to the line where a mark was set, positioning the cursor on the first non-whitespace character.

`{mark}

moves the cursor to the exact position where a mark was set, restoring the line and the column at once.

Note: mm, ``m`: make a handy pair. They set the mark m and jump to it.

Vim's Automatic Marks

Tip52 Tip54