The evolution observed in today's society has put in place many new social realities such as new lifestyles, new needs, new ways of thinking and doing things, new development in science and technology, etc. Taking into account these elements, the researchers, the industrialists have given very significant support to face these different realities that humanity is facing. This book is designed to present an overview of materials in a general way with a special focus on new and innovative materials called intelligent or smart materials. It generally addresses the necessary notion of materials in their natural state by classifying them into two broad categories, namely organic and non-organic materials. Then this book gives an analysis, a description by presenting the multiple uses, the different advantages and disadvantages of the materials and intelligent structures. In this work, we have established a series of different major classes of intelligent materials, for example, shape memory alloys (AMF), Piezoelectric materials, electrostrictive materials, optical fiber, magnetostrictive materials, rheological materials, materials, Chromic, etc.