Social media networks have played a major role in the ongoing pro-democracy demonstrations in Hong Kong. Sky News looks at how they have been used to mobilise the masses across the world in the past decade.
:: Philippines Protests (January 2001)
The ousting of President Joseph Estrada from office quite possibly marked the first time social media was used to help boot a national leader from office.
During his impeachment trial in which he was charged with plunder and perjury, word quickly spread onto the streets of Manila that key evidence would not be used against him following a vote by the Philippine Congress.
Protests were arranged by angry demonstrators through text messages which forced the decision to be reversed, culminating in Mr Estrada's eventual downfall in just days.
:: England Riots (August 2011)
A campaign on Twitter and Facebook encouraged others to get involved in the riots in London and other cities.
However, those who used BlackBerry Messenger to fuel the violence were able to orchestrate the looting across the country through messages which were encrypted and untraceable by police.
It enabled even rival gangs to come together and maximise the terror and carnage which spread from a protest in Tottenham - following the death of Mark Duggan, who was shot dead by armed police - to further areas in the capital, Birmingham, Manchester, Bristol and other cities and towns.
Those angered by the violence and unrest used social to organise the clean-up of their communities afterwards.
:: Russia Protests (2011-2013)
Alexei Navalny, an anti-corruption campaigner, rose to prominence from the mass street protests that preceded President Vladimir Putin's return to power in 2012, via his blog.
Denied access to state media, he harnessed the power of social media instead to reach a new generation of young, politically-minded supporters.
In August 2011, the feminist punk rock protest group Pussy Riot emerged, who used their music videos - which they posted on the internet - to protest against discrimination against women, authoritarianism and Mr Putin's policies.
:: Egypt Uprisings (2011-2013)
From the ousting of Hosni Mubarak in February 2011 - to that of his successor, Mohamed Morsi, in July 2013 - Egyptian activists turned to social media, mainly Facebook, to not only organise rallies and demonstrations, but also to voice their opinions and share updates on the protests.
The movement forced Mr Morsi to turn to social networks like Twitter himself in a last -itch bid to communicate with his discontented citizens, affirm his position and ultimately denounce the army's "military coup" which led to his removal from power.
After the toppling of Mr Mubarak in February 2011, US President Barack Obama highlighted the role of social media in the Egyptian leader's removal at the time, hailing the emergence of "a new generation... that uses their own creativity and talent and technology to call for a government that represented their hopes and not their fears".
:: Venezuela Protests (February 2014)
Both protesters - and the government itself and its supporters - turned to Twitter in a battle to win the hearts and minds of the populace via social media.
As demonstrators marched through Caracas against President Nicolas Maduro's failure to bring down crime, address record staple food shortages and rising inflation, Twitter reported the blocking of images from the protest on its service.
The blockage lasted a day, but in the meantime Twitter offered a workaround for users.
:: Hong Kong Demonstrations (September, 2014)
Pro-democracy protesters in Hong Kong are using FireChat - an app that allows people to chat and send photos to one another, from phone to phone, without the need for the internet or even mobile reception - to highlight their cause to the world.
China's Communist rulers reportedly blocked Instagram on Monday to prevent images of the demonstrations reaching the mainland.
However, FireChart relies on Bluetooth and Wi-Fi to transmit messages between nearby users within a crowd up to 200 feet away - so it cannot be shut down by the authorities.
