The book provides a concise overview of the most important phonetic and morphological phenomena in the history of the German language, such as the second sound shift, umlaut, weakening of unstressed syllables, final-obstruent devoicing, diphthongization, monophthongization, ablaut series, as well as strong and weak nouns and adjectives. New in this edition is the division into sound change and form change following an introductory chapter titled "What is German?" After this, the phenomena are presented chronologically according to Old, Middle, and Early New High German, often referencing Indo-European contexts. Also new is that both the sound and form sections are preceded by their own chapters, which lay the respective foundations, allowing for the description of language change phenomena in other languages with this knowledge.