Robots are increasingly being developed to think and act like humans. But one common human quality that has been difficult for engineers to recreate in machines is humor. Most robots are powered by artificial intelligence, or AI, and machine learning technology. Some have performed better than humans in tests designed to measure machine intelligence. For example, we have reported on experiments involving robots competing against humans in a reading test and in a live debate. Computer scientists have also hoped to give robots technical skills to help them recognize, process and react to humor. But these attempts have mostly failed. AI experts say that in many cases, attempts to make robots understand humor end up producing funny results, but not in the way they were supposed to.