If ever you subscribed to a newsletter then you could not unsubscribe, you have probably been the victim of one of the tricks used by some companies on the web to "catch" to users and make them do things they do not want.
If not they should tell users of Microsoft, which recently forced the software giant to review its policy after showing outrage at a "dirty trick".
In this case a breakdown in the computer configuration led to the last update of the Windows operating system, version 10, automatically install without you requested it.
Like this, there are many tricks that companies use to "catch" to users and get some economic return.
1. The subscription that you can not unregister
This trick will be familiar to anyone who has subscribed to a NEWSLETTER happily (newsletter) or a service and then have found that it is extremely difficult to unsubscribe.
2. The 'Zucking'
The name originates from the name of the founder of Facebook, Mark Zuckerberg.
Refers to the practice of "deliberately create a confusing jargon and user interfaces that deceive users to share more information about themselves than they really want," says Tim Jones, of the Electronic Frontier Foundation, an American NGO that defends the rights of individuals on the Internet.
3. Leading Questions
This trick is to present the user with options confusing when you are asked to tick boxes to buy products or opts not to receive or marketing material.
The companies have deliberately inconsistent alternatives for people to make mistakes, experts warn.
4. A or B?
Many technology companies carry out what is known as evidence A or B, which tested different designs in a website live, at the same time, to see what produces the best results.
This can also be a source of confusion for the user.
It was recently confirmed by Google, which simultaneously experiment with links to their results pages in black and blue to see if the number of clicks (finally took the blue) was increased.