https://www.nobelprize.org/prizes/economic-sciences/2022/press-release/
People may only really know Bernanke as the former Fed chair during the Great Recession, but he's also got a lot of good economic research (his blog is really good too). This year's Econ Nobel goes to him for his research on the Great Depression and to Diamond and Dybvig for their research on banking.
Their research was complementary. Diamond and Dybvig's models showed how banking ultimately works- it creates liquidity for savers and long-term financing for borrowers. Banks as intermediaries have a lot of information to assess borrowers and loan out to productive, sound investments. Absent a banking system, savers might have to access funds they loaned out and cut short an investment project. Their research also explained how bank runs can occur and how deposit insurance can help prevent them.
Bernanke's research helped flesh out explanations for the Great Depression. It is accepted theory at this point that the Great Depression was caused by insufficient money printing. But Bernanke showed how a subsequent banking system collapse from bank runs turned the Great Depression from a standard recession into a severe and prolonged recession. The bank runs caused many banks to close, the remaining banks saw their deposits fall as people were afraid to deposit their funds. Banks in turn became conservative about their lending, which severely curtailed financing for businesses. It was not until measures were implemented to prevent bank panics that the recession began to ease.