CURB PLANETARY OVERHEATING: The purpose of the deal is to hold global warming to "well below" two degrees Celsius (3.6 degrees Fahrenheit) compared to pre-Industrial Revolution levels and to try to cap itat 1.5C.

A LONG-TERM GOAL: The world will aim for climate-altering greenhouse gas emissions to peak "as soon as possible". Countries will then make rapid cuts to as to reach "greenhouse gas emissions neutrality" in the second half of this century. That means net emissions of the heattrapping gases would be zero. But this could be achieved by, for example, planting more trees or using technology to soak up carbon dioxide. Many climate activists prefer a tougher option of banning human activities that produce greenhouse gases, such as burning coal, oil and gas.

A FIVE-YEAR REVIEW: In 2019, the year before the agreement enters into force, countries will take stock of the overall impact of what they are doing to rein in global warming, and revisit their plans in 2020. The collective impact of countries' efforts will then be reviewed at five-year intervals from 2023, after which pledges will be updated.

MONEY, MONEY, MONEY: Bowing to a demand of developing countries, rich nations will mobilise $100 billion (92 billion euros) to help them cope with the cost of climate change. That figure is a "floor" and must be periodically reviewed.

HARM DONE: Low-lying island nationsand poor countries most at risk from climate change-induced sea level rise and other impacts, have won recognition in the draft of the need for help in dealing with losses suffered. While assistance is promised, rich countries will not accept liability.