Updated Nov. 25 at 3 p.m. ET
For roughly half a year, Hong Kong's streets have seethed with discontent. Scenes from the semiautonomous region show protesters, sometimes numbering in the hundreds of thousands, many wearing surgical masks and carrying umbrellas that have come to signify resistance.
The images are astonishing, and the issues that set the protests in motion are complex.
So here's a primer breaking down the major players, why they have poured into the streets and the response so far from China.