Is there life on planets outside our solar system? In this short lecture we dedicate ourselves to this question, which has occupied mankind for thousands of years. For this we dive into the world of “exoplanets”, planets orbiting other stars than the sun. We will look at how many exoplanets have already been found, what their properties are, and explain how we can search for natural and artificial signs of life on them. In the process, we’ll see that there are several ways to detect indications of extraterrestrial life. And if everything goes well, we will manage to get a lot closer to an answer to the big question in the next 20 to 30 years. How exactly do we do that and what do we need to do it? We can only reveal this much: In addition to curiosity and patience, we need impressive telescopes in space.