This course will introduce students to modern imaging modalities used in biology and medicine, with the emphasis on modalities most frequently employed in cellular and molecular biology. The course will offer an overview of basic principles of light and electron microscopy and explain their resolution limits and sources of contrast. We will discuss modality-specific functionally relevant fluorescence molecular probes which can be used for live cell imaging and genetic targeting in microscopy which includes optogenetics and CRISPR-based photoactivatable transcription systems. The course will provide a detailed review and theory of operation of modern advanced light microscopy techniques such as confocal, including line-scanning, light sheet, and STED, as well as multi-photon, super-resolution, and chromatin-sensitive CLASS microscopy. We will also offer an overview of medical imaging techniques, such as ultrasound, X-ray CT, MRI, PET/SPECT, and ultrasound imaging, along with emerging optical imaging and spectroscopy methods. Lectures will be supplemented by visual demonstrations of the microscopy systems and hands-on laboratory work and discussions of the operation principles of those systems.