Before defining what a COP is, we'd better explain how they started.

As you may know, the United Nations is an international organisation dedicated to cooperation between countries to promote peace and solve global problems

During the second half of the 20th century, the environmental consequences of the social and economic models of the so-called "developed" countries at a global level became increasingly evident. Examples of this awareness can be found in the creation of the Club of Rome in 1968 and the publication in 1972 of the report "The Limits to Growth", also known as the "Meadows Report", which warned of the future consequences of continuing with these development models.

To address this issue, in 1992 the UN organised the United Nations Conference on Environment and Development (UNCED), better known as the Rio de Janeiro Earth Summit.

Thus, the United Nations Framework Convention on Climate Change (UNFCCC), a UN legal instrument that is the main international treaty to address climate change at the global level, emerged from this conference and was later established in 1994, with the aim of stabilising greenhouse gas emissions at a level that would prevent dangerous human interference with the global climate system.

The UNFCCC requires the countries that have signed this treaty (currently 197 countries) to hold annual meetings to make progress towards this goal. These meetings are called...

COPs (Conference Of the Parties), are the meetings where the different parties to the UNFCCC, (countries that have signed it), for a couple of weeks, presents their views on the progress and problems detected; discusses and negotiates the actions, procedures and issues to be addressed and their application to achieve international agreements that help us move towards the fulfilment of the UNFCCC's objective. In summary, they are the supreme decision-making body of the UNFCCC.

These conferences have resulted in important agreements to combat climate change; perhaps the most significant is the well-known Paris Agreement, one of the outcomes of the COP21 held in Paris in 2015.

At COPs, each participating country has a voice to present its problems and concerns about climate change, and its suggestions for improving the current situation. It can do this by speaking for itself and/or by forming a negotiating group with other states that have similar interests to it, in order to have a greater say in the negotiations. Below are some of the existing groups (click on this link and see this picture for a more complete list):

European Union (EU): States of the European Union.

The Group of 77 (G77): Group of 134 (originally 77) developing states. Because of China's current global position, this group is sometimes also referred to as G77+China.

African Group of Negotiators (AGN): Formed by the 54 UN member states of the African continent.

Small Island Developing States (SIDS): Group of 40 island states particularly vulnerable to sea level rise.

Least Developed Countries (LDC): Formed by 48 states that, being developing states, are more vulnerable to climate change and less adaptable to it.

It is important to consider that, although the COPs are exclusively about climate change, conflicts of interest of different kinds (economic, political, geographic, etc.) between states are still present (although they are obviously not explicitly addressed).