The advances as well as applications of carbon dioxide laser are elucidated in this book. It provides comprehensive information regarding fundamentals of CO2 laser operation and its upgraded new systems and technologies. Frequency equalization, lasers based on diffusion cooled V-fold geometry, laser producing ultrashort pulses etc. are some of the topics covered in the book. This book also discusses its industrial applications such as welding, cutting, engraving etc. and its clinical applications such as laser treatment, dentistry etc.