问.gitignore中的.DS_Store :不必要？

EN

johndoe@John-Does-MacBook-Pro:~$ mkdir test
johndoe@John-Does-MacBook-Pro:~$ cd test/
johndoe@John-Does-MacBook-Pro:~/test$ git init
Initialized empty Git repository in /Users/johndoe/test/.git/
johndoe@John-Does-MacBook-Pro:~/test$ touch foo.txt
johndoe@John-Does-MacBook-Pro:~/test$ touch .DS_Store
johndoe@John-Does-MacBook-Pro:~/test$ touch bar.txt
johndoe@John-Does-MacBook-Pro:~/test$ touch .DS_Store2
johndoe@John-Does-MacBook-Pro:~/test$ git status
# On branch master
#
# Initial commit
#
# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#
#   .DS_Store2
#   bar.txt
#   foo.txt
nothing added to commit but untracked files present (use "git add" to track)
johndoe@John-Does-MacBook-Pro:~/test$ git config -l
user.name=John Doe
user.email=johndoe@example.com
color.ui=true
core.editor=mate -w
core.repositoryformatversion=0
core.filemode=true
core.bare=false
core.logallrefupdates=true
core.ignorecase=true