All you need is a cheap and reliable backup strategy
A friend recently asked me to recommend an reliable and cheap external hard drive for a Macbook Air. Surprised with the question I immediately asked: "Do you want to use it for Time Machine?" It was clear she didn't know about this backup method. This experience got me thinking and motivated me to share some basic tips regarding backups on your Mac.
First of all, whether you use your Mac for work or for pleasure, keeping a copy of your files is extremely important. The day when you spill a cup of hot tea on your laptop will come. Any accident like this can render your internal hard drive useless and you need to be ready for it.
The most common reaction is to save important files somewhere else. This could be a USB pen drive or a spare portable hard drive you keep for transferring files between computers; perhaps to keep your movies and music so they don't clutter the limited space on your laptop.
The built-in solution is also the easiest
Fortunately, OS X users count with an awesome ally called Time Machine. This is already built in the operating system (from Leopard to the newest Mountain Lion) and setting it up requires very little effort. To use this feature you will need a dedicated external drive just for this purpose.
There are three main reasons why Time Machine is superior than dragging files to your external drive manually. To begin with, Time Machine is automatic. Aside from a quick initial configuration, there's nothing else to do. It will take care of itself, automatically saving changes on your system pretty much every hour.
Second, it saves your personal settings and preferences. This includes all your passwords, emails, folder structure, applications installed, custom shortcuts you use,… I guarantee you don't remember all the time invested in ordering your bookmarks in your web browser, resizing the Dock to your taste, selecting the right keyboard shortcuts and gestures. This will all be saved.
Third, it allows you to peek in the past — hence the Time Machine name — virtually allowing you to go back in time and recover anything you might have accidentally deleted or changed. This is something extremely useful when working with files you edit frequently. You can recover anything in a matter of seconds.
What you'll need to get it working
Going back to the conversation with my friend, you'll need some type of storage to keep a copy of your Mac's local hard drive. Perhaps the most accessible option is a portable hard drive you can plug using an USB cable. There are many optical drives with 1TB these days that will be more than sufficient for the job.
If you want to get fancy, Apple also offers a Time Capsule. This is simply a hard drive you can access wirelessly without the need to plug it to your computer. Having one of these guarantees your backups are always up to date, but for a third of the price you can do exactly the same by simply plugging an external drive with a cable.
Don't worry about the amount of time it takes to copy everything. After the first time, the system will only save those items that have changed since the last backup.
Since my friend has a Macbook Air equipped with USB 3.0, I've recommended a Hitachi Touro 1TB external drive that was on offer at Amazon. The USB 3.0 means the data transfer between your computer and the backup drive will be significantly faster than with an older device using the USB 2.0 standard.
Useful tricks for using Time Machine
Before you start your copy, here are a couple of things to remember. Time Machine will keep a copy of your Mac every hour for the last 24 hours. These will be changed to daily for the past month and weekly until you fill the disk. What this tells you is that you should be plugging your backup drive before and after doing some important work so it gets the latest changes that happened in the last hour. You shouldn't worry too much about the amount of time it takes to copy everything. The system is smart and will only backup those items that have been changed from the last backed up copy.
A good practice in data backup is keep redundant copies in case something fails. Considering the sale price of that Hitachi Touro drive, I wouldn't mind getting a second one to have a second Time Machine backup drive. Mountain Lion is capable of understanding you want to use a second drive and will manage this automatically for you.
Next in this guide: If you already have an external hard drive to use only for Time Machine backups you can continue reading the second part.