Time Machine, the Backup Software You Should Be Using

Makes automatic backups simple on your Mac

Time Machine's user interface screenshot
Use Time Machine to go back in time to recover a lost file. ​ 

Using Time Machine as the primary backup for your Mac is a no-brainer. This easy-to-use backup system not only lets you restore your Mac to a happy working state after a disastrous crash, but it also lets you ever-so-easily restore individual files or folders you may have accidentally deleted.

In addition to restoring a file, you can go back in time to see what a file looked like an hour ago or at any time or date in the recent past.

About Time Machine

Time Machine is included with all Mac operating systems beginning with OS X 10.5. It requires an internal or external drive onto which it automatically backs up your Mac as you work. It works with Apple's Time Capsule as well as with other hard drives.

Time Machine's user interface and ease of setup make it a backup application you're likely to use and continue to use.

Time Machine was a revolutionary approach to backup when it was first introduced. The revolutionary part wasn't the backup process or how creative the user interface was or even how well Time Machine pruned old backups. All these things had been seen before in backup applications. What made Time Machine a winner was that it was so easy to set up and use that people actually used it. That's the revolution. Mac users are actively backing up their computers without having to think about the backup process.

Setting Up Time Machine

Setting up Time Machine amounts to selecting the drive or drive partition you want to dedicate to your backups. Once you do that, Time Machine takes care of just about everything else. The setup options are limited to selecting any drives, partitions, folders, or files you don't want to include in your backups. Time Machine notifies you when it deletes old backups unless you turn off this notification. You can also decide whether to add a status icon to the Apple menu bar.

For the most part that's it. No other settings are required to set up or figure it. Click the Time Machine On switch or Back Up Automatically depending on the version of Time Machine you use in your Mac's Time Machine Preferences, and your system will be backed up.

There are other options you can make use of, such as using multiple drives to store your Time Machine data, but the advanced settings are hidden away and not needed by most casual users.

How Time Machine Performs Backups

The first time it runs, Time Machine performs a full backup of your Mac. Depending on how much data you have stored, the first backup can take quite a while.

After the initial backup, Time Machine performs a backup every hour of any changes that occur. This means you only lose an hour's worth of work in the event of a disaster.

Some of Time Machine's magic lies in how it manages the space it has for backups. Time Machine saves hourly backups for the last 24 hours. It then saves only daily backups for the past month. For any data that's older than a month, it saves weekly backups. This approach helps Time Machine make the best use of available storage space and keeps you from needing tens of terabytes of data just to keep a year's worth of backups on hand.

Once the backup drive is full, Time Machine deletes the oldest backup to make room for the newest. This is important to realize: Time Machine does not archive data. All data is purged eventually in favor of more recent backups.

User Interface

The user interface consists of two parts: a preference pane for setting up the backups and the Time Machine interface for browsing through backups and restoring data. The Time Machine interface is fun to use. It displays a Finder-type view of your backup data and then presents the hourly, daily, and weekly backups as stacks of windows behind the most recent backup. You can scroll through the stack to retrieve data from any backup point in time.