Will your child ever be four years old again? Definitely not. Will you ever get married again? Maybe, but you can never repeat that wedding moment when the maid of honor's hair caught fire while she was smoking a cigar. Memories like these used to be stored in elaborate photo albums or more likely shoved into a shoebox and stored in the attic. There they stayed, rarely perused, but safe and accessible for the next stroll down memory lane.

Today, your digital life consists of digital photos, music, and home videos from your camcorder, and they're all stored very near your fingertips, on the 120GBto-500GB hard drive in your PC or Mac. But what if you have a problem with your computer (pick one), and you have to bring it down to the local big-box store where you bought it. At that point the usual way the tech "fixes your problem" is by reformatting the hard drive and reinstalling Windows or Mac OS X. Your memories, your treasures, your digital life are all gone. There has to be a better way.

An external hard drive is the closest thing we have today to a digital attic. Sure, you can use DVD+R or (shudder) CD-R discs to back up your files, but do you really want to look for "Disc 15, backup 23 March 2003" to recover that picture of Uncle Nick with the funny hat on? With capacities of 80GB to over 1 terabyte, external hard drives let you back up all of your memories, and you can either save it in a safe place like a closet or even off-site at a relative's house, or use it to transfer your files to another computer. Smaller 'portable' or 'pocket' drives are easy to move, just in your pocket or using a laptop bag. But even the larger 500GB drives are only the size of a child's shoe box, so all external drives are portable, to a certain extent. Searching for and recovering a lost file is as simple as hooking up the drive and dragging the file back from the search window. Windows Vista and Mac Os X 10.5 have built-in backup utilities, but these drives come with backup software as well. It's win-win all around.

External drives need to connect to your computer somehow, and all of them have USB 2.0 ports, which can also work at slower USB 1.1 speeds if your system is older. FireWire 400 (aka i.Link) is another connector technology, about the same speed as USB 2.0. FireWire 800, as the name suggests, is about twice as fast as FireWire 400. The fastest interface is eSATA, which is theoretically as fast as your internal SATA hard drives, but so far support is limited to a few high-end motherboards or an add-on card you may need to buy separately. Each interface is built into the drive, and it's up to you to pick the right one for your setup (Macs have FireWire and USB, most PCs come with USB only).

You can start simply with the Western Digital Passport (160GB), which is a "pocket" drive with a notebook's 2.5-inch hard drive mechanism in its sleek black case and has fewer interfaces and no power to worry about. Pocket drives are USB only, and work well with both notebook and desktop computers. They're also a great way to carry your backup in your travel bag. (Imagine your laptop dying midway through a trip to Singapore and you understand the value.) Western Digital adds utilities such as WD Sync, which can make sure you have the most current versions of your files on the drive.

Users with security issues (perhaps you have nosy coworkers or kids) will want a secure drive such as the LaCie SAFE (500GB). Its 500GB capacity can hold pretty much all of your photos and music, and still have room left over for videos. The integrated fingerprint reader is effective: After you set it up, it works to keep unauthorized users away from your confidential data even if they move the drive to a PC that doesn't have the utility software installed. No security system is perfect, but the SAFE will keep prying eyes away.

The Iomega UltraMax (640GB) is a different beast. Its twin 320GB drives can be set for either RAID 0 (640GB capacity, best drive space and performance) or to RAID 1 (320GB capacity, safe because if one drive fails the other still has all your data). The UltraMax has USB and both flavors of FireWire, making it a good choice for those working on both Macs and PCs.

The biggest dog in this pack is the CMS Velocity2 RAID Backup system (1 terabyte). Like the UltraMax, the Velocity2 has two drives and the option for RAID 1 (500GB) and RAID 0 (1TB). Where it differs is that the UltraMax is sealed, meaning that if one drive fails you need to send the whole thing to Iomega service. The Velocity2 has a pop-off front panel and pop-out drives. You don't even need a screwdriver. You can swap a drive in about 30 seconds after powering the system down. The ability to replace drives quickly is important for people who make their living with their computers, like graphics freelancers and database developers. The Velocity2 is a pricey drive, but if you're working on multimillion-dollar projects, it is well worth it. USB, FireWire 400/800 and eSATA all make the Velocity2 one connected drive.

External hard drives can be the insurance policy you take out on your digital life. You can't place a price on your memories, particularly if they are lost to the ravages of PC glitches. Spending between a hundred and a thousand dollars is a small price to pay to keep your priceless digital life safe. Read on for our take of the latest ones.

REVIEWED IN THIS STORY:

Western Digital MyBook Pro
This is a sleek choice for the design-conscious household. It combines innovative touches, such as a circular indicator on the front that lets you know how much drive space you have left, with flexibility, offering USB, FireWire 400, and FireWire 800 interfaces.

Western Digital Passport (160GB)
The Western Digital Passport is a good choice for a user who needs scads of portable storage. It works with most PCs and Macs and is perfectly sized for travel.

LaCie SAFE (500GB)
This drive stores tons of data and helps you keep it secure from prying eyes. Its fingerprint reader gives you a reasonable level of security for a shared computer or a computer in an accessible area.

Iomega UltraMax (640GB)
A quick "drop-in" solution for professional Macs, the Iomega UltraMax (640GB) gives the Mac user speedy, portable storage. PC users can use the UltraMax too, but it's really a Mac-oriented drive.

CMS Velocity2 RAID Backup system
It's a matter of time before the drive(s) in your mission-critical desktop or workstation fail. The Velocity2 RAID Backup System is a "belt and suspenders" type of backup drive, but if you're the kind of user who regularly burns out hard drives, it's the drive you're looking for.

Not quite as large as the 1-terabyte behemoths roaming the hard-drive pride lands, the Western Digital MyBook Pro ($330 direct) comes with a still-way-roomy 500 gigabytes (half terabyte) of storage. This is enough for hundreds of hours of DVD-quality video and hundreds of thousands of MP3s or digital photos, not to mention other types of files. The MyBook Pro has a handy front panel indicator that shows how much space you have left on the drive without forcing you to right-click on your desktop's hard-drive icon. This indicator could have been designed better (you need to install a driver for it), but it does work. The MyBook Pro works with three of the most common connection methods (USB 2.0, FireWire 400, and FireWire 800). It's a great addition to a multimedia-oriented laptop or desktop, particularly if you've got a lot of files to work with, and as such, earns an Editors' Choice nod.

Click here to read the full Western Digital MyBook Pro review.

The Western Digital Passport (160GB) ($179.99 direct), the latest in the company's Passport series of portable hard drives, comes in a higher capacity than earlier models and with a new "piano black" exterior. It's a good companion to your notebook (particularly dark ones such as the Lenovo ThinkPad and the Apple MacBook in black), as well as a data-toting device for someone who needs to take work home but doesn't want to carry a notebook every day.

Click here to read the full Western Digital Passport (160GB) review.

The LaCie SAFE Hard Drive 500GB ($250 direct) is one of a growing number of computing devices that can help you or your business to secure your secrets. Your company's books, personal documents, and anything you'd rather not reveal to the world are prime candidates for storage on this drive. A biometrically secure drive, the SAFE should protect your information from casual data thieves. The drive can be physically locked down with a cable, and it doesn't work if you remove the drive mechanism from the casing.

Click here to read the full LaCie SAFE Hard Drive 500GB review.

It's clear at a glance that Iomega designed its UltraMax 640GB hard drive ($340 direct) with the Mac professional market in mind. The UltraMax's distinctive silver case and "cheese grater" front panel are compatible in appearance with professional-model Macs. (These include the Apple Mac Pro, the MacBook Pro, the Power Mac G5, and the PowerBook G4.) Though the UltraMax can also service a Microsoft Windows PC, it has the three interfaces (USB, FireWire 400, and FireWire 800) found on these Macs. The drive has a decent dollar-per-gigabyte ratio, as well as speedy RAID 0 or safe RAID 1 settings, so it is suitable for the demanding multimedia user on a budget. The UltraMax is a big step in the right direction for a hard drive maker that's had its share of missteps (think Iomega Jaz, ZIP disks, and the Iomega ScreenPlay). For that and much more, it earns our nod for Editors' Choice.

Click here to read the full Iomega UltraMax Hard Drive (640GB) review.

As storage needs grow ever larger, 1-terabyte (TB) class drives are coming out of the woodwork to fill the void. CMS Product's Velocity² RAID Backup System ($1,119 direct) is one of those drives you'll want to have if you've invested a lot of time and money in your data. The Velocity² is a two-disk RAID external system, which makes it a prime candidate for video editors and other users who need blazing drive-transfer speed. It gets the job done, and it does it fast, earning an Editors' Choice.

Click here to read the full CMS Velocity² RAID Backup System review.