What is Sustainable Finance?

I am trying to get a better idea of what is going on with the economy. I was reading an article that mentioned sustainable finance, and I am trying to find out more about this. What exactly is it? Is this a theory of how to keep the economy in better shape? I really wish I would have studied economics a bit more so I would have a good idea of what I should expect when it comes to the economy, and how long this downturn is expected to last. I keep finding different information and I really don’t know what to believe.