A tuple is a fixed fixed-length list containing elements that need not have the same type. It can be, and often is, used as a key-value pair. A row (sometimes called a record) is the set of fields within a table that are relevant to a specific entity.
The stem wall on a concrete foundation is essentially the supporting wall that joins the foundation of a building to the vertical walls of the structure that is constructed atop the foundation.
A pony wall, sometimes referred to as a split wall or stacked wall, is a single wall composed of two separate wall types; one built above the other. There are two ways to create a pony wall in Chief Architect - by drawing it using the Pony Wall tool or by specifying a normal wall as a pony wall. Select Edit> Default Settings from the menu.