This is the same as .exrc which is use for VI & EX but it's used for VIM which is a freeware version of VI that runs on DOS and UNIX machines.
For DOS machines you have to tell it where the file _VIMRC is with this statement in your AUTOEXEC.BAT file. _VIMRC is used instead of the file .exrc
set VIM=C:\mike\bin
I put the following commands in my _VIMRC file. most of them are the same as for VI with one or two that don't exist in VI.
version 4.0
se ic
se nowrap
se noerrorbells
se nowrapscan
se vb
se showmatch
se ruler