High-harmonic generation is a phenomenon in nonlinear optics where intense laser light is focused into a medium, typically a gas, causing the generation of harmonics of the original laser frequency. This process can lead to the generation of very high-frequency light pulses in the extreme ultraviolet and soft X-ray regions of the spectrum. High-harmonic generation has various applications in fields such as spectroscopy, microscopy, and attosecond science, where the ability to generate very short pulses of high-frequency light is important for studying ultrafast processes in materials and molecules. Research in the area of high-harmonic generation involves studying the mechanisms and dynamics of the process, optimizing the generation of high harmonics, and exploring new applications for the technology. It also involves developing new techniques and tools for controlling and manipulating the characteristics of the generated high-harmonic light pulses.