On Tuesday, I explained how to archive all your data from old PCs. Now I would like to make your life even simpler by vastly cutting down on the amount of data that you need to preserve. Here are some things you do not need to keep:

All 4 virtually identical photos of every subject, snapped in burst mode on your digital camera. Choose the one that is in focus and throw the others away.

All the virtually identical photos of your child's birthday party. Pick one of them opening a present, one of them playing with it and one of them blowing out the candles on the cake. Put those on a single album page and throw the rest away.

All the virtually identical years of birthday party shots. Your child doesn't change much between 4 and 8 years, or 12 and 15. Keep years 1, 2, 3, 8, 15, university graduation and Christmas at age 9. The rest you can discard and regenerate later with morphing software, if necessary.

Any photos of children younger than 12 months, whether yours or someone else's. All children look virtually identical at this age anyway. This picture will do perfectly well to represent them all.

All video footage of anything involving family members. If anyone falls over or reveals their underwear, send it to You've Been Framed. Everything else goes straight in the Recycle Bin. You may keep some CDs labelled "Cousin Stacey's Wedding" to appease your wife, if you like but these can be blank because they will never actually be watched.

Any porn. This is already archived perfectly satisfactorily on the internet and leaving it there until you actually need it causes much less trouble in the long run.

Any mp3 files of songs not currently on your iPod. You might have a thousand CDs in your collection, but that's just because you never throw anything away. You only ever play tracks from your 20 most recent purchases and Pandora (assisted by Hotspot Shield, if necessary) will cover you for anything more eclectic.

Any software you have the original discs for. You can just reinstall this.

Any software you don't have the original discs for. You can just "borrow" the discs from Dave, like you did last time.

All letters. Nothing you write is worth keeping for posterity.

All emails. Especially the ones to Suzie in Accounts.

Any files not covered in this list. They are probably just viruses and Trojans anyway. Especially all that junk in Windows\System. You can delete that right now.*

*Don't do this.