本书以随笔的形式以北京的四合院为描述对象，阐述北京民居的地方史、风俗史、建筑史及变化沿革，及其所蕴含的民族文化。(The book uses the form of essays to describe Beijing's Siheyuan courtyards. It describes the history of the living places of Beijing's citizens, as well as the history of customs, architecture, and change, in addition to its national culture.)