The IEA (International Energy Agency) Solar Heating and Cooling Program is a group of people who work together to make things that use energy from the sun to heat or cool stuff, like houses and buildings.
They research and study new ways to make these things work better, cheaper, and more efficiently. They also make sure to share what they learn so that others can use it too.
For example, they might create a design for a solar panel that is really good at catching the sun's energy and turning it into heat. Then they would tell other people about this design so that they could use it too.
So, the IEA Solar Heating and Cooling Program is all about finding new and better ways to use solar energy for heating and cooling things, and sharing that knowledge with others.