One thing that you hear all the time is how important it is to backup your computer. You don't really know how important it is until data loss happens to you. The sad thing is most people still don't do it. Even Apple thinks that backing up is so important that they made it one of the main features in OS X Leopard (Apple calls it Time Machine). Right now your hard drive is sitting there. It's filled with all those irreplaceable digital photos, downloaded music and movie files, e-mails, and other documents waiting to be lost by a tragic Mac emergency - a hard drive failure.
If you are lucky enough to have a Mac running Leopard, then congratulations, you have everything you need for backing up your Mac, almost. The other thing you need is a place to put the backup. If you have a Mac tower, you can install a second internal hard drive, an inexpensive part you can get online or at any store that sells PCs. The easiest route, and for those with iMacs, laptops, minis, etc., is to get an external hard drive. This can either be a Firewire or USB 2.0 based unit (I personally like Firewire but they are a bit more expensive and harder to find). USB 2.0 drives are popular with Windows PCs and can be found almost anywhere.
To use Time Machine, the backup drive must be at least the same size as the main hard drive or larger. When Time Machine first runs, it will backup your entire system, which does take a while. After that, Time Machine will backup only the files that have changed over time at an interval you set. As an example, say you've spent a week working on a presentation for an up coming meeting. Over that week, Time Machine has backed up this file several times, in effect saving different versions. If that file suddenly disappeared you can go back in time and retrieve it. Another benefit in the way Time Machine works is that you can go back in time to get an older version of a file, like one that was worded differently or the one before you deleted a page of text you thought didn't work.
After you've installed or attached a new drive, Leopard will see it and ask you if you want to use it for Time Machine. OS X walks you through setting up the drive so Time Machine can use it for backup. This only takes a minute, but the initial backup can take a while. When you are ready to set up a new drive for Time Machine it might be best to do this just before bed, or at the end of the work day before you head home.
If you don't have Leopard yet, it's not the end of the world. For those running Panther or Tiger, OS X 10.3 or 10.4, there is a solution, although not automated as Time Machine. You still need an extra internal or external hard drive that is the same size, or slightly larger, as the main drive. There are two free programs available that will make an exact ''clone'' of any Mac drive. One of the easiest to use utilities is called Carbon Copy Cloner.
Carbon Copy Cloner 3.1.1 works with Tiger or Leopard, but they still have version 2.3 available for download for Jaguar and Panther. Carbon Copy is not an automated backup system, like Time Machine, what it does is create a complete duplicate, a 'carbon copy', of any Mac hard drive. Just tell it what drive you want to clone in the pull down menu and then what drive to copy to. Hit the clone button, it will as for your OS X password, and away it goes. Cloning a large drive can take a while, a big drive could take a couple hours. After it is all done, this backup is a complete copy of your main drive and is even bootable (USB 2.0 drives cannot be used to boot OS X - internal or Firewire drives can).
Another cloning tool is called SuperDuper. This works just like Carbon Copy, but if you purchase a registration code, under $30, you get some extra features. Notably you get scheduling, Smart Update (which saves a lot of time), Sandboxes, scripting, and more. SuperDuper requires OS X 10.4 or better.
For anyone that relies on his or her Mac, cloning is a powerful tool. Hard drives do fail and having a bootable replacement drive means that your Mac will be up and running in a matter of minutes instead of hours or even days. Of course, if your main drive fails, you do lose everything not backed up since it was cloned. Cloning is an important tool, even if you have Time Machine running.
For even more data protection, it's important to store that backup off site. If the absolute worst thing was to happen, say a fire or flood, then it's possible that both the Mac and the backup could be lost. Having an external hard drive allows you to take it with you. Externals are available in standard and portable models. The standard model uses a 3.5-inch drive and need to be plugged into and A/C outlet. Portable models uses a 2.5-inch laptop drive and can usually get power right from the computer. Portable models are smaller and lighter, but they usually don't hold as much data. Plus they are usually more expensive.
These are just a few ways to help you protect important, and sometimes precious, data on your Mac. If you have Leopard and Time Machine is active, you have some pretty good protection. If you use your Mac for business, then cloning is an important step to help keep you going in case of a Mac Emergency.