The world’s biggest polluters are increasingly relying on “carbon offsets” to claim they are reducing their climate impact and reaching net zero. Simply put, carbon offsetting involves an entity emitting greenhouse gases into the air paying another entity to pollute less. For example, an airline in a developed country that wants to claim it is reducing its emissions could pay to protect part of the Amazon rainforest. This would – in theory – “undo” some of the airline’s pollution. As Carbon Brief has detailed in a newly released explainer , the world of carbon offsets is complex and murky – with a single carbon offset project often involving a number of different players and stakeholders in countries scattered around the world. The complex nature of carbon offsets has given rise to a wealth of technical and often difficult-to-understand terms, phrases and acronyms. (The authors are Daisy Dunne  and Josh Gabbatis)