You may have seen that Wikipedia and several other major websites are "blacked out" today in protest against the US Congress bill called SOPA.
But what is SOPA, how does the black out work and will it affect UK sites?
SOPA is the Stop Online Piracy Act, officially known as H.R. 3261 and was introduced into Congress by US senator Lamar Smith.
It is currently passing through US Congress for approval, and was introduced for debate on 26 October 2011, has had one hearing on 16 November a "mark-up period" on 15 December.
What will it do?
The bill will allow copyright owners take sites down with a court order.
Search engines will be barred from linking to sites deemed to illegally hold copyright material, and internet service providers will have to block access to these sites.
Streaming copyrighted content without permission will become a crime. The penalty will be a maximum penalty of five years in prison for ten infringements in six months.
Why are some websites protesting SOPA?
Many sites like Google and Wikipedia say the SOPA bill will turn the internet into a police state, as they will be required to check whether every user is linking to material of which they own the copyright.
Jimmy Wales told the BBC "venture capitalists that they would find it hard to invest in new start-ups in the user-generated content space."
He went on to say: "Wikipedia would become very difficult if it were necessary for us to police everything that users were doing against some blacklist of websites."
How will it affect us in the UK?
Search engines will have to comply with the bill by removing links to sites displaying contentious copyright material.
Paypal and credit payment services like Visa and Mastercard can be cut off.
As Wales points out, start-ups that focus on user-generated content may find it hard to gain funding, and will have to devote significant resources to checking all material for copyright.
Can I black out my site?
Do you know Javascript? Add this line of code to your site to join the black out.
How does the blackout work, can I get around it?
The blackout is designed to give protest the bill, and give you an idea of what the internet could be like without sites that feature user-generated content, like Wikipedia.
You can get around the Wikipedia blackout by pressing escape as the page you need loads, or use Wikipedia on your smart phone.
Read on for a more in-depth look at SOPA.