This book is the third volume of the popular four-part series on experimental physics by Professor Demtröder. The teaching content of atomic, molecular, and solid-state physics is presented in a clear, comprehensible, and as quantitative as possible manner, following the concept of the series. Worked examples in the text, exercises at the end of each chapter, and detailed solutions at the end of the book help students to grasp the material and encourage their own engagement. Illustrations, definitions, and important formulas are designed in two colors to highlight the essentials clearly. Many illustrations and some color plates on selected topics contribute to motivation and make working with this book enjoyable. The fifth edition has been corrected, revised, and is presented in a new, clear format.