I was looking out for the actual meaning of the word "Oppression". Though it is a very broad term, the main context remains almost the same.
According to Wikipedia, "Oppression is the exercise of authority or power in a burdensome, cruel, or unjust manner. It can also be defined as an act or instance of oppressing, the state of being oppressed, and the feeling of being heavily burdened, mentally or physically, by troubles, adverse conditions, and anxiety."
The Universal Declaration of Human Rights and the concept of Human Rights in general were designed to limit oppression by giving a clear articulation of what fundamental freedoms any system should allow to all of the people over whom it has power.
When oppression is systematized through coercion, threats of violence, or violence by government agencies or non-government paramilitiaries with a political motive, it is often called Political repression.
Several movements across the globe have arisen that specifically aim to oppose, analyse and counter oppression in general. It might take ages for a movement to defeat oppression. But sooner or later the movement wins..
Note: The photographs are from Indian Administered Kashmir and Palestine. The final photograph (last on) shows an Indian policeman chasing Raashid Wani a cameraman working for an Indian owned media channel Sahara Samay who was severely beaten while covering events in the Srinagar city a few weeks back.