Privacy and security are something of a hot button for people at the moment, so I'd like to introduce you to a resource called Lightbeam. It's an interesting Firefox add-on that tells you how many websites you have connected with in the course of a period of time. Now you might say that you know how many sites you've connected with, because those are the ones that you have visited, but not so fast my confident friend! When you visit a site your details can get passed onto 3rd party sites which you're simply not aware of. These sites can track what you're interested in, and can affect the content that you get on other sites - that's why if you do a search in one place for something you then start to see adverts for the same thing popping up on other sites that you visit.
Lightbeam can let you know the extent to which this is happening. I started running it in the background this morning and just carried on working as normal. After an hour or so I took a look at the data that it had collected, and this is what I found:
So although I'd actually only pointed my browser at, and gone to 26 sites my details had been passed onto 186! Some sites are obviously worse than others, and you can use Lightbeam to discover which sites are passing on your details. With Hootsuite for example - a Twitter client - you wouldn't really expect it to be passing on details would you, but in actual fact it's passed on details to 21 other sites. These are not sites that I've visited myself, and many of them I simply don't recognise, so it's not a case of seeing a site come up in a tweet or anything.
As they explain: "The default visualization is called the Graph view. As you then browse to a second site, the add-on highlights the third parties that are also active there and shows which third parties have seen you at both sites. The visualization grows with every site you visit and every request made from your browser."
It's not something that particularly bothers me, but I know that other people will be unhappy with it. It's not a tool that I'll use all of the time, but may try it out every now and then, but it's certainly illuminating.