This chapter provides an in-depth introduction to the principles and methods used in scattering imaging. It starts by explaining the basic concepts and physical principles behind light scattering, as well as the key mechanisms that make scattering-based imaging possible. The chapter then moves on to more advanced imaging techniques that make use of scattered light, with a focus on how spatial characteristics of scattering media and transmission matrix calibration help in image reconstruction. Additionally, it introduces methods for separating scattered light in open space, including techniques for spatial domain separation, single-frame image separation, light field data processing, and optical coherence tomography. Overall, this chapter offers a detailed yet accessible overview of both the theory and practical aspects of scattering imaging.