Thanks in part to organizations such as the Free Press Action Fund, the movement for free online expression - for proof, look at the millions of people who struggle to save Net neutrality.

But there is an important problem that many defenders of free expression are not yet aware of because they are generally hidden under the elegant interfaces of our devices and software: DRM or the management of digital restrictions.

DRM is a wide range of technologies that give the manufacturer a special digital control over the ways people use it. They exist since the 1990s having colonized personal computers, smartphones gaming consoles, cars, tractors and more.

DRM is more harmful to the freedom of interference with our use of media such as videos, books and music.

This DRM is the underlying technology that keeps you from copying Amazon Kindle e-books on Barnes and Noble Nook, downloading a movie clip on Netflix for use in a documentary or swapping a song from Spotify into a new song music.

DRM exists primarily so that Hollywood studios, large music labels and streaming services like Netflix and Spotify can use it to incite the spoiled spending only if it could make full use of the media.

Media DRM hurts cultural expression.

First, DRM introduces arbitrary barriers to cultural barriers. There is no way of knowing how many musicians are unable to reach a potential audience because DRM blocks their music, no longer no way of knowing how many books are not read or how many moviegoers are unable to deliver important messages . Foul to DRM that prevents the use of other movie clips. In the worst case, DRM can make the media completely inaccessible, as Amazon demonstrated when Remote Removed 1984 copies of George Orwell from thousands of Kindles without notice.

The second DRM path detrimental to free expression is a little more complicated. In order to prevent people from breaking DRM and accessing the media on their own terms, the music and film industries, as well as US trade officials, have managed to lobby through anti-circumvention laws " in the whole world. These laws make it illegal for anyone to discuss DRM disposal methods - or even mention the details of how DRM systems work. For many public interest technologists, this barrier to freedom of expression makes it more difficult for them to protect the public from malware and criminals. This also creates a dangerous precedent by expanding the types of expression that the government can restrict.

Whenever there is a restriction on freedom of expression, we must ask ourselves whether it is justified. For example, some would argue that limiting hate speech is justified. But limiting freedom of expression because Hollywood studios, big music labels and streaming services want to support their business models? This is something we should never accept. We must abolish the DRM, first by repealing anti-circumvention laws - such as the 1201 Millennium Digital Copyright Act - that give it special protection.

I am delighted that Sunday Free Press Action Fund is taking part in the International Day against DRM, an annual action day organized by my group, the Free Software Foundation. To protect your right to free expression, take action on Sunday at The mere fact of a publication on social networks helps to expose this problem.

Paul Emison for DayNewsWorld