What is 'loss and damage' compensation at COP27 and who should pay?

Nearly 200 countries gathering for the U.N. climate conference in Egypt are expected to lock horns over whether rich nations should pay compensation to vulnerable states hit by climate-fuelled disasters.
 

The COP27 summit follows a year of such disasters, from floods that killed more than 1,700 people in Pakistan to drought withering crops in China, Africa and the U.S. West. That has intensified developing country demands for a special "Loss and Damage" fund. But with rich countries resisting such calls, the issue has been stalled for years.
 

Here's where things stand ahead of COP27.
 

What is "loss and damage"?