This is the second book of the Mishneh Torah of the Rambam, Rabbi Moshe ben Maimon. Laws of Tefillah.
This chapter explains that wherever there are ten Jews, a synagogue must be built, specifying where in the city it should be built and how it should be constructed. The synagogue and house of study require respect; whether students may eat there or hold a eulogy there, ensuring they are not treated as a barrier; and whether they may enter with their walking sticks and sandals. The chapter also addresses the rules concerning a destroyed synagogue: whether it can be demolished to build another and whether it can be converted into a house of study. It covers what can be purchased with synagogue funds, the difference between a village synagogue and a city synagogue, whether it can be given as a gift, and whether the city square is considered holy.