My preferred back up medium is an external hard drive. They are very easy to use.

I like Apricorn portable hard drives. I also like the HP Media Smart Home Server if you have several PCs and Macs.

Do a search on www.pricegrabber.com - an aggregator, to get a feel for the best prices. My favorite tech shopping sites are www.newegg.com www.amazon.com and www.zipzoomfly.com .

Below is an article by one of my favorite tech journalists, Leo Laporte:

Backup Basics

Every system needs backing up. Don't wait until you lose your data to learn this important lesson. 

Your hard disk will crash. Count on it. It happens to everyone eventually. And when it does you will be glad you have a backup copy of all your data.

You do have an up-to-date backup, don't you? You don't? Never fear. Here are the simple rules of data recovery for people who hate to back up.

Where Do I Store Backups and What Should I Use?

I strongly recommend using some form of removable media for your backup. If you can't take it with you, it's not a backup. I know a famous author who lost an entire novel because her backups were stored next to the computer when her house burned to the ground.

Forms of removable media

You can back up to floppy disks if you have no other choice, but floppies aren't reliable for long-term archival storage. And filling dozens of floppies is so time-consuming, most people will put off backing up until it's too late. Many users want to emulate businesses and back up to tape drives. Tapes are cheap, and their huge capacities make it easy to back up an entire hard drive. But I don't like tape backups because you're never sure if the data is really there. I prefer to have long-term archival storage of my data. For that I use a CD recorder. These devices cost as little as $75, with blank CDs costing pennies a piece when bought in bulk. Since each CD stores 650-700MB, I can back up all my data monthly for very little cost. CD storage is compact, compatible with nearly every PC on the market, and likely to last for several decades at least. Recordable CDs are as close as you can get to backup nirvana.

CD-RWs (CD rewritables) present another alternative to storing your backups. CD-RWs cost a little bit more per media than CD-Rs but are well worth it. CD-RWs allow you the option of dragging and dropping directly to the disc just like you would when copying files to a floppy disc. Older removable storage mediums such as Iomega's Zip or Imation's SuperDisk are suitable if you already have the required drive. These disks hold 100-250MB or 120-240MB respectively -- plenty of space to back up all your irreplaceable data. Best of all, your data is stored on the disk normally, so it's easy to verify that the copy actually took. Your money is better spent on a CD-R/RW drive if you don't already own a Zip or SuperDisk drive.

Backup methods

I use a simple shareware program called Second Copy to automatically back up my data every few hours to a Zip disk in my machine. But this is an old practice I've engaged in for ages. I have three disks I rotate daily, taking the most recent to work with me. This way I always have three copies of my data, one of which is offsite in case of a major disaster. Another means of backing up data is to purchase a second hard drive or create a special partition on your current hard drive.

There are a number of programs, such as PowerQuest's Drive Image, Norton's Ghost, and Dantz's Retrospect that image all the contents of your entire hard drive and create a second version of it. This type of software is ideal only if you have a second hard drive, though. Keep in mind that backing up to a separate partition on the same hard drive isn't going to be recoverable if your hard drive crashes.

What Should I Back Up and How Often Should I Do It?

Businesses make backing up simple. They buy big tape drives and back up absolutely everything all the time. When the inevitable hard drive collapse happens, the system administrator can restore the work in a matter of minutes. For businesses, where every minute of downtime means dollars lost, that might make sense. But most individuals aren't willing to pay the money or take the time to back up everything all the time. What should you back up? For the rest of us, the essential rule of backing up is, "Make a copy of anything you can't otherwise replace." That means you make copies of all your personal data, such as documents, image and media files, email, financial data, saved games, and anything else that's important to you. Don't make copies of Windows or your applications (unless you no longer have the master disks). If you copy the contents of a program folder, it usually doesn't operate the same as if it were installed. If you lose your hard drive, you'll have to take a few hours to rebuild it from the original program disks. That's not the end of the world. The main key is to have a recent copy of your precious data, so that you can restore it in the event that something does go wrong. You'll want to back up some things every time you make changes. For example: I make a copy of my Quicken data every time I balance the checkbook. Other things can be backed up weekly or monthly. I'd strongly recommend backing up all your data at least weekly and saving a copy of that backup offsite. If you can't get to it weekly, then religiously try to do it at least once a month.

Keep files in one folder

You should have one folder where you store all your documents. Mac users will want to create one called Documents and will want to start getting in the habit of storing all their work inside this folder. Windows automatically makes a My Documents folder, and most Microsoft programs will automatically store their data inside this folder unless directed not to. Not all programs automatically save documents to the My Documents folder. One critical exception is a program such as Intuit's Quicken. It stores data in its own program directory, unless you save it elsewhere. So if you're using Quicken, right now, before you forget, open Quicken and save a copy of your data to the My Documents folder. Once you do that, Quicken will continue to keep it there. If you're religious about directing programs to store documents in the My Documents folder, backing up will be much simpler. Nearly everything you want to back up will be inside it. The key concept you should remember is that it's easier to back up one folder instead of having to hunt through your entire hard drive for files you can't live without when it comes time to back them up. There are a few other things you might also want to back up.

Where Do I Find My Data Files?

Here's a list of common data files and where to find them: Saved games: Inside the game program's directory you should find a folder called "Saved Games" or something similar. There's no clear method of describing where a saved game is stored, since each game manufacturer uses a different system. If you are unclear, consult the game's documentation.

Email:

Locations vary. Eudora stores its email and address book in .mbx files in the main Eudora folder. Outlook Express lets you specify the location of its .dbx mail file, so it could be anywhere. Netscape Messenger defaults to "C:\Program Files\Netscape\Users\your name\Mail." Outlook stores everything in a .pst file. The easiest way to locate a lost file on your system is to use the Find Files application. From the desktop, press F3 to launch the program. To find all the Outlook Express email boxes on your system just search for *.dbx. The asterisk is a wild card that tells the search tool to find all the files ending with .dbx on your system. Templates, fax cover sheets, and documents: You may have put a lot of time into these. It'd be a shame to lose them. If you don't already, get in the habit of keeping these in the same folder. When you save a document, make sure you specifically save the file in the designated backup folder.

Internet bookmarks and favorites:

Netscape defaults to "C:\Program Files\Netscape\Users\your name\bookmark.htm." Internet Explorer stores them as individual files in the C:\Windows\Favorites or C:\Documents and Settings\User Name\Favorites directory.

Preferences and settings:

They're scattered all over your hard drive, usually in files with the .ini extension. You probably don't need to back up Windows .ini files, but you might want preferences from other programs. And don't forget to jot down your dialup networking and TCP/IP settings while you're at it. You may have other important data hidden away on your hard disk. It's not a bad idea to take a walk through your drive to see what else is there. You can simplify matters by doing a search of your disk by file creation dates. Look for new files, since new files were most likely created by you. The moral of our story is all computers fail eventually. And they always seem to do it when you need them the most. Protect yourself by backing up. You'll be glad you did. I promise.