A question that has haunted stupid people forever.  And now I, Christ Sol the amazing, lay your curiosity to rest:
For god's sake, back the #@!!&^ thing up!

But how? Why? And when?

The answers to your frantic questions can be as personal as your venereal diseases.

But, before we start, a special message for the IGLA (Internet Geeks/Losers Alliance):

Suffer.

HOW?

There are as many backups as there are Elvis Impersonators. In fact, backup methods have a lot in common with Elvis impersonators.  Most of them are dismal failures shunned by the community, some of the higher-class ones may actually bring some satisfaction into your life, and both burn readily with enough lighter fluid. 

These are the most popular forms of MEDIA to backup to:

CD ROM
These little critters can store up to 650MB of data, which is pretty much yer average directory of naughty hentai girls being molested by "evilly sensual" tentacled creatures.

DATA TAPE
These come in different sizes, ranging from the prehistoric Colorado 150MB tape system, to the Gwen Stefani (or Russell Crowe if your that way inclined) of tape drives, the multi-gigabyte DLT. 

NETWORK DIRECTORY
If you're lucky enough to be on a decent LAN, your systems administrator may get up from his super-supreme family size extra-cheesy pizza and 416th round of Return to Zelda (or whatever they play) to copy the files in your personal space.  They will very reluctantly go hunting through old volumes, and are likely to secret copies of whatever you have to laugh at and/or blackmail you with later, so maybe it's best you don't keep your Purity Test results in your home directory (an in joke for BOFH fans).

FLOPPY DISKS
For the masochists out there. One standard hard disk = 8.5 Gb = 8,704,000Kb = 8,500 diskettes. Hope you have nothing planned for the weekend. Loser.
 

Software:

MS-DOS BACKUP.EXE: 
Bahahahhaha.  How many Microsoft employees does it take to screw in a lightbulb? None, they've been kept in the dark for years.

Microsoft Backup:
"Partition? Whats a Partition?"  The K-Mart, Diet Coke, Blue Light special of Backup programs.

Anything labeled NORTON or SYNMANTEC: 
Usually a good bet. These cookies know what they're doing.

NERO Burning ROM or similar:
Kinda like "Choose your Own Adventure" for manual backups. If you know how the directory strucutres work, and have a decent CD-R or CD-RW, go with one of the CDROM burning programs. No bells or whistles, but quite effective. If you dont ^%$* up.

Why?

Because accidents happen, dickbrain.

When?

How long is a piece of string? What time does a train leave? How much is Ronald McDonald going to scream when I finally get my chance to give him an enema with a handful of Ginsu knives?

It's all up to how often u update stuff, how stable your machine is, how much your media is going to cost, and how mission critical your data is. Me, I have about 600-700Mb to backup (a CDROM's worth), and I back up once a month. Costs me AU$2.80 a month for peace of mind.  Then again, the Aussie dollar is worth about 2 Baht or something stupid right now. So. yeah. Cheaper. I think.
 
 

IMPORTANT:

Backups are like contraception:
 

• You can be fairly safe winging it with only one method for the majority of time, but it's really Russian Roulette when it comes to continued use.

• The method depends on your equipment, and the size of what you need to protect (yes, shanus & greck, we're STILL talking about backup media here, dirty monkeys)

• The right kind of backup can, over time, improve the health of all your bits n pieces.

I have to go take my pills now.

~c~
 

(C) 2001 Christ Sol. So Screw you.

RUSSEL CROWE:
PHWOAR!
 

DLT's (Something Something Tapes):
... Oh.