external drive so that you can keep it in another place. The way I look at it, backups are

for 2 reasons. First, to protect myself against me. Second, to protect me against everything

else.

The first category is for things like accidentally erasing a file I need,

corrupting a file or erasing its contents by doing something stupid while running a program,

etc. For errors like these I’m going to realize what I did pretty much immediately, and

having a backup right at hand gets me going again (although most programs these days can be

configured to create a backup copy automatically; you just rename the backup to the original

and restart).

The 2nd category is all other hazards. Hard drive crash is the most

obvious. But there are plenty of other dangers worth protecting against. Two biggies would be

theft and fire. If your backup drive is in the same room (or building) as the computer, it can

be lost too. The loss of *everything* would be so catastrophic that I’m willing to lose 2-4

weeks worth of my most recent work in order to guarantee that I haven’t lost it *all*. So I

keep my external drive in a different location than my computer and back up to it every few

weeks.