Dr Hannah Wakeford, University of Bristol, UK The study of exoplanets, planets that orbit stars other than the Sun, is at the forefront of the public imagination in space and an exciting field of research. The question "how do stars and planetary systems form and evolve?" is one of the biggest in Astronomy, and is at the root of one of the most important questions in science today: "How did we get here?". To resolve these questions we need to observe, interpret, and understand the nature of planets beyond our Solar System. In this talk I will go through the methods, observations, and the physics behind some of the interpretations we are making about the nature of these strange new worlds. As an observer I will show some of the work we have been doing measuring the transmission spectra of giant exoplanet atmospheres looking for the tale-tale absorption of water vapor and the presence of exotic clouds. I will discuss some of the challenges associated with the measurement of atmospheric abundances, a brief look at the role clouds can play in understanding dynamics and chemistry, and what future measurements can help further constrain our understanding of planetary atmospheres. Those unable to attend the colloquium in person are invited to participate online through Zoom (Meeting ID: 942 0262 2849, passcode 792771) using the link: https://zoom.us/j/94202622849?pwd=dGlPQXBiUytzY1M2UE5oUDRhbzNOZz09 Dr Wakeford will be based at the Max-Planck Institut fuer Astronomie during her visit to Heidelberg, and will be available for meetings by arrangement with her host, Laura Kreidberg (email@example.com).