I've been thinking a little further since my last post on the subject of open and closed systems, and I realised I forgot to mention the largest problem of all with closed formats - preservation of data.

The recent deaths of some well-known writers who published large swathes of material online has lead many to think about what will happen to the data they place on the internet after their death. Domains expire, databases are purged. Books can be destroyed by catastrophe or malice, but data can be destroyed simply by not paying attention to it.

Documents that ran on the oldest computers will not be readable by their modern counterparts unless you convert them to an open format which can be used as a master down the road, allowing important online publications and other digital information to be accessible centuries later.

So what if we lose a blog or two? So what if an informative amateur astronomy website dies from lack of funding? So what if government records kept digitally are lost at some point - we get a clean slate, right?

You know, I'm half inclined to agree. I just love getting rid of things. My parents were hoarders, a side-effect of being raised shortly after two world wars, but I become more and more of a minimalist every day.

And there's a lot of data the world won't miss. But there needs to be ways to save the important stuff. And it's not always easy to judge what is important stuff and what isn't.

Our National Archives has a nifty little tool called Xena aimed at preserving documents. They have been working industriously on keeping our country's data stored in ways that wil lbe useful to us in the future.

Do I think the iPad is going to destroy history as we know it? Of course not. This discussion began because of the talk about the iPad after its press day yesterday, but it's not about the iPad anymore.

Many old NES games from the 80s are now playable on the console giant's latest console, because they kept their old game development files and were able to convert them to a format playable on their new system, re-selling them to customers. But smaller game companies who don't have the resources of Nintendo to do those things with their own products - particularly seeing the companies who made the products might not even exist anymore - may never re-release their games for new systems.

No, that isn't a devastating thing. It's a little sad, but it won't dramatically alter the path humanity takes towards a Bright New Future and a New Tomorrow. But the relaity is that we are moving more and more towards content produced by individuals and smaller organisations who will rise and fall like the tides over our digital landscape. They will leave, and unlike Marcus Aurellius' diary, their words may become unretrievable centuries down the track.

Yes. This is quite the tangent. Tangents are delicious, especially when you pick them fresh from the tree.