A group of Iranian Twitter users are writing political slogans on banknotes, and using them to spread protest messages.
What it means: In December last year, protestors took to the streets of Iran's capital, Tehran, to protest against the government. Most of the protests were organised through a messaging app, called Telegram. The app's now being threatened with closure. In fact, in Iran, Twitter is also banned (though leaders have accounts, and some people access it through a 'proxy' server).