In recent days, especially regarding revelations about the NSA’s practices with phone calls, the words ‘Meta Data’ have been mentioned a lot. You might also have heard of it in relation to Search Engine Optimisation, but what it is all about?
In a Nutshell
Meta data is extra information added on to whatever file/data you have, usually hidden in the background, aimed at adding more context to is.
- a photograph might have the date it was taken, what the camera was, the settings used for the photo, maybe even its location
- a conversation on a phone would have details of which number called which, the time and duration, via what network, etc
- an email sends a bunch of extra info such as what connection you are using to the Internet (IP address), via which provider
- a web page might have a list of keywords, a description field and possibly other info such as which program made it, copyright, etc
Of course you can read more geeky definitions of Meta Data on WikiPedia and other more reputable sites!
Should you care?
The majority of people aren’t aware this data exists and hence it seems like a bit of an irrelevancy, but it is starting to become a profitable industry and relies on you giving up data. Indeed it can be quite helpful, eg. the upcoming iOS7 will use it along with some photo-recognition software to group together photos from the same event.
Currently meta data is mostly used by industry to identify general patterns for a group of people (eg. mobile phone companies selling location data from your phone in anonymised blocks of 50 people) it has been shown that it’s relatively simple to start breaking even such ‘anonymous’ blocks down to the individual level.
These kind of privacy issues are why you need to be aware of what you’re sending out. Yes, it is another ‘privacy’ thing to worry about but the reason we have so many of these is that most of this technology is brand-new, unchartered and under-legislated waters. Once you give up data it is hard to get it back so it is best to understand what you’re giving out.
A few examples might help to illustrate:
- A Word Document automatically adds details such as authors, who revised it and when, often including postal addresses you used when registering software
- Some sites strip out meta data for speed reasons meaning that you it gets difficult to prove you took that photo and hence media outlets might suggest they can use it for free/ without copyright (more on that in another post!)
- The elusive founder of McAfee was caught-out when a reporter using an iPhone forgot to remove the location data from the photo, which gave up his whereabouts to the authorities (you can turn this off in settings)
Meta Data is growing …
In general as bandwidth and storage increases, more and more ‘meta data’ is being added to files and databases. So what might seem like a few bits of data now is really starting to grow exponentially. A 6Mb photo can easily have 100kb of meta data attached … in fact, it could be a lot more than that as one of the techniques for reducing file-size on a website is just to strip off this meta data, it can be as much as half the size of the file.
There are tools out there allowing you to alter the meta data you provide, most notably for images. However that would take up most of your time and isn’t practical (though do check out what is set in your Microsoft Office under ‘File > Info’), moreover privacy really comes down to what you share with whom. As a general rule if it is on a social network it is public; if emailed it can be forwarded; if on ‘cloud storage’ then you’ve shared it although it should be private.
Um so what can I do about all this?
Firstly, “don’t panic Captain Mainwaring”, in fact meta data can be (as it was designed) really quite useful. As services are working to determine the right usage of it you’ll probably be ok.
A few tips:
- when you next look at an Office document check the ‘properties’ (under File > Properties or ‘Info’) and see whom it says is making your documents and owns them
- be aware when uploading images to social networks that you might not own/ be able to trace them anymore so perhaps keep those amateur photos for display somewhere else
- start tagging your photos – putting information like where you took something, what camera, etc can really add to the utility of the file and make it much easier later when sorting through thousands of images