Good news for Twitter users: you can now download every nugget of wit and wisdom you've ever posted to the service.

I've already downloaded mine, and it's brilliant.

Who can forget beauties such as: "I am seriously considering going to see The Cult", "Heh. Probably :)", "Yikes!", my initial impression of the Sanyo Xacti HD1000, or the news that an Elbow concert in Manchester was "astonishing"?

Somehow I doubt the British Library's going to come banging on my door, demanding to exhibit five years of my moaning about EasyJet, TicketMaster and next door's dog to a Tweet-hungry world, but that's not really the point.

What matters is that Twitter has made it as easy to get my stuff out of the service as it was to put it there in the first place.

As Instagram reminded us this week, that can be quite important.

Know where your exits are

The problem with sharing your stuff online is that things change - so for example Instagram changed its Terms of Service this week, upsetting many, and services such as Facebook appear to change their T&Cs every other login.

If you decide that you don't like the changes, or if the service is taken over by someone you don't approve of, or if you just prefer a newer competitor, then moving your stuff from one service to another shouldn't be an enormous hassle.

There's another reason you might want to have a copy of your stuff: backup. It's rare, but online services can and do mess up, so the occasional big download can give you peace of mind.

Credit where credit's due here: the likes of Google and Facebook make it easy to get your stuff back from their services, and that's particularly useful if you use them to store and share your photos. Other services such as Flickr and Instagram are a bit less helpful, although third parties have stepped in to provide the download features they lack.

As long as you use someone else's products to store your content, there's the possibility that one day they will turn round and do something appalling or annoying, or just fail to keep up with the rest of the planet - so what looks perfectly fine today could become perfectly awful six weeks, six months or six weeks down the line.

When you're storing stuff on other people's services, don't just look at how easy it is to upload and share your stuff. Look at how easy it is to get it all back again.