Photo by fczuardiThe Software License and the EULA (End User License Agreement) have always been part of software. It contains the rights people have regarding the software, often limiting those rights as much as possible. It’s being a contractual document, Eula’s often contain a lot of legal jargon, which usually is gibberish to ordinary human beings. The question is, do they have to be this difficult to read?

I’m not going to answer that question of course, since I’m no legal expert, but readability – which happens to be a part of usability – is part of my expertise. It can be measured. Many scientists studying language have come up with formula’s to calculate the level of difficulty of a particular piece of text. The most well known of these scientists is Mr. Flesch who invented the Flesch Reading Ease test. The result was the following formula:

The results from this formula come in categories:

This table showed you that the higher the score, the easier the read… (source of both formula and table is Wikipedia)

Luckily there are tools to calculate the score on your texts (like this one which was used to calculate the values below) and even websites like this one. (And also note that there are other ways to calculate readability which I’ve kept out of this article to keep some readability…)

Let’s get back to the Eula. Is it any good, Is it readable and how do different Eula’s compare? I created this little table for your enjoyment:

As you can see, the most readable license in this list is the GPL v2. The worst is the Microsoft EULA for Windows XP. Interestingly, the very open BSD license in it’s simplified FreeBSD version doesn’t do much better than the MS Eula. Also note that the Microsoft Public License isn’t that bad a read, meaning that you don’t need to be a MSc to understand what it tells you.  Since I didn’t check every license in the world, this is just an indication. Want your favourite license added to the list? Just leave your comment and I’ll update the table (when I find time to do so…)

An interesting question is the following legal one (please leave your comments!): If a license requires you to have more education than you actually have, can you actually be bound by it’s terms? In other words: If you can’t understand because they made it too hard, and you still accept, are you bound to it? And how about: Do we need to force companies to create their license documents with a minimum Flesch Reading Ease score of 60? Should we have a law about that? Should an ‘average’ person be able to understand this sort of documents since that same average person is also using the software? Should licenses be written in a way that helps the reader and user of the software? I think they should, How about you?

to further compare free licenses on other characteristics a good source to look is this one.

I am currently not aware of tools and formula’s to calculate readability in other languages than English. If you are aware of one of those, don’t hesitate to leave a comment as well…

I hope you enjoyed this post!

UPDATE: A discussion has started partly caused by this post on IusMentis (dutch).