This book is a friendly introduction to TEX, the powerful typesetting system designed by Don Knuth. It is addressed primarily to beginners, but it contains much information that will be useful to aspiring TEX "wizards". Moreover, the authors kept firmly in mind the diversity of backgrounds that characterizes TEX users: authors in the sciences and in the humanities, secretaries, technical typists... The book contains a careful explanation of all fundamental concepts and commands, but also a wealth of commented examples and "tricks" based on the authors' long experience with TEX. The attentive reader will quickly be able to create a table, or customize the appearance of the page, or code even the most complicated formula. The last third of the book is devoted to a Dictionary/Index, summarizing all the material in the text and going into greater depth in many areas.