Micro- and nanofabrication technologies have realized gears in the current information-intensive society. The industry is giant and attractive, and a lot of scientists and engineers from different fields from physics, electronics, chemistry, and materials sciences are involved. Although there have been a numerous number of books have been published on micro- and nanofabrication, the most of them look so much specialized and complicated, assuming the readers’ good background of microelectronics and/or semiconductor physics, which makes difficult to start learning this new attractive field. In this book, the basics of micro- and nanofabrication are described on the basis of the concept of “using gases as a fabrication tool.” This book assumes the entry-level mathematics, physics, and chemistry of undergraduates, or even high-school students, in science and engineering courses. However, necessary theories are plainly explained to help the readers’ further reading of specialized books. This book is an attractive guide for students, young engineers, and anyone who are getting involved in micro- and nanofabrication.