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Whatever your backup or sync scenario, ChronoSync has got you covered!

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To Sync or Backup


ChronoSync is your Mac's complete data management utility that allows you to efficiently synchronize or backup files and folders from one disk location to another. You can synchronize or backup files to most any device you have access to from your Mac's Finder window. But you have to begin by deciding whether to sync, or to backup. The answer may indeed be both, depending upon your circumstances. This tip explains the difference between Sync and Backup, and gets you started using ChronoSync.



All the data on a Mac is stored on the hard drive. This may be a spinning disk, or a solid-state drive (SSD). These appear in Finder as 'Devices' and may be labeled “Macintosh HD” or something similar. Hard drives are also referred to as Disks, Volumes, and HD's. Data can also be stored on external hard drives, Network-accessible Storage (NAS), iPods, iPhones, mobile phones, web servers, discs, and a lot more. These may appear in Finder as some of your 'Favorites' and 'Shared' devices. Your data on these devices is organized into a structure of Folders. The folders can contain other folders, and/or data files.

When using ChronoSync and choosing something to sync or backup, you are choosing a 'Target'. This may be a Drive or Volume or maybe a folder or sub-folder on one of your drives. The point to remember is if you can browse the device or folder using Finder, you can choose it as a 'Target' in ChronoSync. So in ChronoSync, a Target is one of your devices, maybe your startup volume, or one of the folders located on one of your devices.


All of the data on your hard drive, or any device for that matter, is really just a bunch of files. These files have many descriptive names: Applications, Packages, Utilities, Folders, Documents, and many more. For the most part your Mac can be divided into four basic sections; Applications, Library, System, and Users. Each of these sections is a folder at the root of your hard drive that stores a bunch of files.

  • Applications - Where all your applications are stored. Application files are the programs that you use on your Mac.
  • Library - Where all the files are stored that need to be accessed by the Operating System, Applications, and all the Users.
  • System - Where the OS X Operating System or 'OS' is stored. All of these files are the ones that run your Mac.
  • Users - Where all the Home folders are stored. This is where all the data files are stored for each user.

When using ChronoSync, the data that is synced or backed up includes the files and any sub-folders that are contained in the 'Target' that you choose.


Your Home folder or User folder is a special folder on your Mac. The Home folder isn’t actually named “Home”; its name is the same as the short name specified in your user account and it is created as a sub-folder of the 'Users' folder mentioned above.

Your Home folder is the place where all the data and preferences related to your user account are stored. It's your HOME. All of your documents, mail, music, movies, pictures are stored inside your Home folder. Even your Desktop is a sub-folder of your Home folder. Every user on your Mac has a unique Home folder. It serves to keep everyone's stuff separated from all the other Users that have an account on the Mac.

For the most part only the "OS", which runs your Mac, and Applications, which all Users share, are stored outside of the Home folders. However some people may store files in various places all over their hard drives. If this is the case you should get organized and store all your files in the Home folder.

When using ChronoSync, keep in mind that your most important data is located in your Home folder. This is true for each of the users on the Mac. You can always restore your OS and reinstall purchased applications, but you don't want to have to try to recreate the data files you have in your Home folder. So, when syncing or backing up, the best place to start is at 'Home'!



Syncing should be considered when you need to use files on both targets - the source and the destination. Files get copied from a source to a destination and then back again. Syncing is typically used to keep data files the same on two different Macs such as in the case of keeping some Documents synced between an iMac and a MacBook.

A good sync scenario is that you have some Documents you have been working on using your iMac. You now need to travel and will be carrying your MacBook on your trip. Before you leave, you synchronize the Documents to your MacBook using ChronoSync. Now you have the Documents on the MacBook to use during your tip. While traveling, you make changes and update the Documents. Upon your return, you synchronize the Documents from your MacBook to your iMac.

The above scenario can be handled by creating a bi-directional sync document.

The two Targets you choose are your local 'Documents' folder on your iMac, and the 'Documents' folder in your home folder on the MacBook. Save the Sync Document and then run it before your departure to sync the 'Documents' folder to your MacBook. Run the Sync Document upon your return, and the files that you changed during your trip are synchronized back to your iMac.


Backup should be considered by everyone. You backup files when you need to maintain a redundant backup of your files in case something goes wrong. When backing up, files get copied from a source to a destination. You typically never use the files on the destination other than to restore them in the event a file is accidentally deleted or becomes corrupt.

A special type of backup is the 'Bootable Backup'. This backup scenario involves making a duplicate of your startup volume. This provides you the ability to 'boot' or startup your Mac using the Bootable Backup volume in the event your startup volume becomes corrupt or disabled. The advantage of a bootable backup is that you have a complete duplicate of your OS, Applications, and all user accounts in one place and you can use it to have your Mac running in moments after a failure.

A good backup scenario is that you want to keep a duplicate copy of all of your Documents. By making a regular copy of your Documents to a backup device, you have a safe copy in the event a Document is changed and you want to revert back to the older version, a Document becomes corrupt, or you accidentally delete a Document. In the event you need an older or working copy of a particular Document, you can use ChronoSync to locate the Document and 'Restore' it to your working Documents folder.


Sync when you need to keep two sets of files that are actively modified in sync with each other.

You don't want to synchronize System or Library files outside of your Home folder because these files can vary from Mac to Mac. You don't want to synchronize Applications because all Applications should be installed and updated from an installer or Software update. You should only synchronize files in your Home folder and, more importantly, you should only synchronize some of the files in your Home folder using ChronoSync. There is some Managed Data inside your Home folder you should not sync using ChronoSync. Managed Data are files in your Home folder that are structured into databases like your Address Book, iTunes, iPhoto and Bookmarks.

To learn the basics of synchronizing, watch our video "Setup and run a ChronoSync sync syncing two Macs".


Unlike synchronizing, which limits what files you can sync, you can (and should!) back up all the files on your Mac. If you fail to regularly do this, eventually you may be one of those people we all hear about who lost their data because they were not diligent about backing up. You can backup to internal drives, external drives, Macs, PC's, iPods, iPhones, network, or web storage. Many people use Time Machine to backup their Mac and if you do that you are better off than most who do not even backup at all. However, Time Machine does have some limitations that ChronoSync does not have.

First, Time Machine can only back up your Mac. It cannot back up data stored in other locations, like external drives. Second, it cannot make a bootable backup. Third, and most notably, Time Machine stores the files it backs up in proprietary format. That means you can only view and restore backed up files using Time Machine. ChronoSync store files exactly in the same way on the destination as on the source. That means you can view and restore backed up files without ChronoSync. So what you see on your Mac is exactly what you see on your backup. In fact, this is the main reason why so many users like ChronoSync for backing up.

ChronoSync does have one limitation that Time Machine does not. Although ChronoSync archives deleted and changed files, it does not have the ability to restore these files to a specific time like Time Machine can. Instead, ChronoSync allows you to restore older files by file version. So every time a file gets deleted or changes, ChronoSync archives the older version in case you need it again. To learn the basics of backing up, watch our video "Creating a Bootable Backup of Your Mac Using ChronoSync".

Backing up your Mac

If you want to find out more information on backing up your Mac then get the book Take Control of Backing up Your Mac by Michael Cohen.