What is a .DS_Store file?

I frequently get asked about the purpose of .DS_Store files by Windows System Administrators who have a few Mac’s on their networks. Here is my explanation:

What is a .DS_Store file?

.DS_Store files are used by Mac OS X to store folder specific metadata information. They are created in every folder that Mac OS X Finder accesses, even network volumes and external devices. Folder level customizations are stored in the DS_Store file, things like custom icons, icon placement, icon size, window placement, list views, custom background pictures or colors, etc. DS_Store files are intended to be unobtrusive, which is why they have a . in front of their name, which indicates to UNIX file systems that the file is invisible. Most Mac users will likely never see a DS_Store file at all.

What happens if I delete the .DS_Store files?

If you delete .DS_Store files from the Mac folders, you will lose that directories folder specifics; things like icons, window placement, background pictures, etc, will be lost. While there is no significant harm (except losing the folder metadata) to deleting DS_Store files, unless you have a very specific reason to delete them, you should keep them in place since the Mac OS X Finder uses them. Deleting the files is really only necessary in some specific Windows+Mac shared networking environments.

Can I stop the DS_Store files from appearing on network drives?

Yes, by executing the following command in the Terminal:

defaults write com.apple.desktopservices DSDontWriteNetworkStores true

It is rather easy to stop .DS_Store file creation on network connections but it is rarely necessary, read for more information.