What do you call an array whose components are arrays themselves?

The correct term for an array whose components are arrays themselves is commonly referred to as a multi-dimensional array. Multi-dimensional arrays allow for the storage of data in a matrix format, meaning that each element in the array can also be another array. This structure is useful for representing more complex data arrangements, such as grids or tables, where you might want to capture rows and columns of data.

While "two-dimensional array" is a specific case of a multi-dimensional array, it does not encompass all types of arrays that contain other arrays. Multi-dimensional arrays can include arrays with more than two dimensions, such as three-dimensional arrays, which might be used in applications like 3D graphics or simulations.

The term "nested array" can also describe an array containing other arrays, but it is often used more informally. It does not have the same formal definition as multi-dimensional arrays which are specifically structured.

A composite array, on the other hand, is not a standard term within the context of arrays and could refer to a variety of structures depending on the programming language or framework being used.

Thus, multi-dimensional array covers the broader definition and is the most accurate answer for an array containing other arrays.