( CNN ) -- Iranian protesters have found a new outlet to mobilize and take action . The presidential election has proved how much opposition supporters can demand change without necessarily taking to the streets . Just give them a computer and an Internet connection and watch what they can do . Supporters of defeated Iranian presidential candidate Mir Hossein Mousavi protest in Tehran on June 13 , 2009 . At the height of the protests and disorder in Tehran on Saturday and Sunday , Twitter was used to give graphic accounts to a worldwide audience - even if they were a maximum of 140 characters . Tweets from `` Change for Iran '' were among several that offered real time updates : `` ... my friend saying more than 100 students arrested , I ca n't confirm this but the numbers are high . bastards just attacked us for no reason , I lost count of how much tear gas they launched at us ! ... we have now some students with urgent need of medical attention I 'm calling out to all ppl who can come here do n't leave us . '' Some Iranians are already veterans on social networking sites with loyal followings . They offer the world a unique voice : free , unfiltered and very different from what the Islamic Republic of Iran 's media propaganda offers viewers and readers . Internet service is available in Iran but it is still in its infancy . Available in homes , on hand-held devices and in select cafes , the Internet is slow and unreliable at times , says blogger and aspiring journalist Ali from Tehran , a supporter of opposition leader Mir Hossein Mossavi . This makes services such as Skype almost impossible to operate . Watch the role technology has had in the election » . Still , it provides users with an outlet to the outside world as the country waits for broadband and wider wireless coverage . With the absence of text messaging and mobile services -- both were cut off across the country on and around election day and were still blocked on Sunday -- Twitter proved to be the most reliable communication technique between people inside Iran and millions of others on the outside thirsty for any update . Twitter has enabled people to express to the world their hopes for the elections , excitement at the chance of exercising their right to vote , jubilation in President Mahmoud Ahmadinejad 's camp and shock and disappointment among Mossavi 's supporters . Now they 're keeping the Twitterverse ablaze with information about Moussavi , his challenge to the election results and his intent to request their annulment . Moussavi 's supporters comfortably outnumber Ahmadinejad 's on Twitter but both are represented . Facebook is also very popular in Iran , says Ali . He wholeheartedly believes that Facebook was the reason behind what he describes as a successful campaign by President Ahmadinejad 's main rival . Ali says Moussavi campaign managers organized supporters , planned gatherings and garnered support through Facebook pages dedicated to the Reformist candidate . `` His Facebook page got huge amount of fans on it , pictures spread extremely fast , '' says Ali . It was used on Saturday and Sunday to organize and announce street protests , to send out warnings about police activity , but especially to keep followers abreast of his whereabouts . They were the first to talk about his forced house arrest . President Ahmadinejad also jumped on the social networking bandwagon ahead of the race . However , his popularity there pales in comparison to that of Moussavi . Both candidates ' pages remain a main source of information for updates and breaking news . In fact we 've seen many cases of news breaking on Facebook first while confirmation came later , including Moussavi 's house arrest and Ahmadinejad 's planned addresses . According to Iranian bloggers , website filtering falls under the oversight of the Intelligence Ministry in conjunction with the Ministry of Information and Iran 's judiciary . Bloggers complain that at times the ministry filters words like `` violence , '' `` unrest '' and `` democracy . '' Recently , Ali believes the censors were filtering content based on a candidate 's name . Moussavi supporters claim filtering particularly targeted their candidate after his popularity soared and authorities feared he would pose a serious challenge to Ahmadinejad . Another challenge for Iranians comes from the U.S. Because of its sanctions against Iran , some services like video conversations are not allowed . So , it 's a tap dance sometimes to figure out the best way to talk to someone in Iran . People do n't like to use landlines or mobile phones for fear of their calls being traced . They do n't like e-mails as they can leave a trace . They do however feel comfortable with services like Google Talk . They find it safe , as no one can see what they look like and with common Iranian first names like `` Ali '' and `` Shahrzad '' , as my main contacts are named , they find a way to communicate with the world as few Iranians have done before .
People protesting presidential election use Facebook to mobilize and take action . Facebook used to give graphic accounts of protests to a worldwide audience . Social networking sites offer the people a unique voice : free and unfiltered . People do n't like to use landlines or mobile phones for fear of their calls being blocked .