What does this command line that starts with "1, $" do in Vim?

I have a shell script created by someone else which I am currently trying to understand and there is a line in it which is

vim -c "1,\$s/MAJOR_VERSION = ./MAJOR_VERSION = $1/" -c "1,\$s/MINOR_VERSION = .*/MINOR_VERSION = $2/" -c "wq" $f

I know what it does is change MAJOR_VERSION = . to my input ($1), but I don't understand what the

"1, \$s

at the beginning means. The corresponding vim command from terminal would be :\s/MAJOR_VERSION... etc, so what does the $s do in this case?

1,$ defines the range on which your substitute command s/../../ is applied. 1,$ means 'from the first to the last line'. See :help range in Vim for more.