Then there are websites that Iran really doesn't like. Those are blocked, too, and the people behind them are often punished.
Among them is the Sufi website "Majzooban-e Noor," which covers news about the Nematollahi Gonabadi dervishes in Iran. The group, considered the largest Sufi order in the country, has come under increasing state pressure in recent years. Conservative clerics describe Sufi interpretations of Islam as deviant.
"Majzooban-e Noor" has closely covered the crackdown on dervishes, becoming an invaluable source of information for Sufis and others interested in their plight.
Recently, the website has felt the full wrath of Tehran, as officials have arrested and jailed those behind it.
Last week, seven of the website's staff members, including its managing editor and a photojournalist, were sentenced to jail terms ranging from seven and 1/2 to 10 1/2 years. They were convicted of acting against national security, spreading propaganda against the establishment, and insulting Iran's leaders -- the same charges that Iran often brings against political activists and intellectuals.
The seven dervishes have been banned from membership of groups and political parties and from engaging in any kind of media activity, including on the Internet, for five years.
They had been in custody for the past two years and were reportedly subjected to solitary confinement while awaiting their sentences.
Some 20 people have been arrested in connection with the Sufi webpage since 2011.
The authorities have also recently sought to increase pressure against the editor of "Majzooban-e Noor," Farhad Nouri, who fled to Turkey two years ago.
Nouri told RFE/RL that his mother, Farzaneh, was sentenced over the weekend to two years in prison and three years in exile in Khuzestan Province for her affiliation with the website, acting against national security, and disrupting public order.
"My family and I dismiss these charges as baseless," Nouri said. "When they arrested my mother in September 2011 it was only because they were after me. My mother is a dervish, but she didn't have anything to do with my human rights and media work. Until I left Iran, she didn't even know how to use a computer."
Nouri's mother spent three weeks in prison in 2011, where she was reportedly interrogated, mainly about her son's media activities. She was released on bail.
Nouri also told RFE/RL that he has been threatened and told through intermediaries to discontinue his website and stop spreading information about the repression of Sufis.
He says the pressure he is facing has made him even more determined to continue his work.
-- Golnaz Esfandiari