"They are really fluid, and sometimes they get together very quickly and they disperse very quickly, and it really looks like water is flowing and flowing through different parts of the city," says Masato Kajimoto, an assistant professor of Journalism and Media Studies Center at the University of Hong Kong, referring to the protestors.
Kajimoto says the instant messaging app Telegram is playing an important role in enabling protestors to be so fluid. Telegram was launched in 2013 by Russian programmers. One of its key features is security. It is heavily encrypted and users can set messages or accounts to "self-destruct". Functions such as group messaging and public channels mean users can distribute messages to multiple people instantly. Telegram groups can have up to 200,000 members.
Kajimoto says the app surged in popularity, mainly among young people, once the protests started to escalate. Participants discuss times, locations and methods of protests in Telegram groups.
Kajimoto says there are countless groups and channels, some with hundreds of thousands of members. This app means the protest movement doesn't need specific leaders to organize rallies, and allows for protests to spring up quickly, sometimes in multiple locations.
The content of the rallies are decided in a democratic manner. The messaging app has a polling feature so group members can vote on where to go and what to do there.
Kajimoto says this year's protests differ significantly from the so-called Umbrella Movement of 2014.
The Umbrella Movement was the opposite of “water,” he says. "They were in one place, and demanding certain things with a group of people as their leaders. And that failed. If you look at this strategy this time, it's 180 degrees the opposite of what happened then. It's a leaderless movement, and they go to many different places around Hong Kong."
Telegram also allows people to support the movement without physically joining in the street rallies.
The message below is a list of security numbers for condominium entrances. It was disseminated via Telegram. It is believed to have been posted by a supporter who wanted to allow demonstrators to take refuge when they are being chased by police. One message listed lawyers that protesters should contact if they are detained by police. Another had a number to call if they need someone to drive them away quickly.
Rikkyo University Professor Toru Kurata researches politics and civil society in Hong Kong since the territory's reversion to China. He says the government's reaction to the Umbrella Movement, including crackdowns on free speech and banning pro-democracy candidates Legislative Council elections, left people feeling powerless. He says latest protests unleashed people's pent-up anger and broadened the support base.
But Kajimoto says the strengths of Telegram could be seen as a weakness too. Since there are no obvious figureheads of the protests, it's not obvious who the government should negotiate with.
"I don't know who could possibly represents the protesters," he says. "They have five demands, and the government knows that. But at the moment nobody knows who should be at the negotiating table, so there is no way for the two sides to meet each other and try to have a real conversation to try to end this crisis."