The result of a data structure query.  A type tree
  graphically shows the structure of data types used
  in your code.  For example, the declaration of a record
  consists of a record and some record components.  Each
  record has a type, which may be another record, a
  pointer to the same record, a basic data type such
  as an integer, and so on.  A type tree shows the
  relationships of the record to its components and the
  components to their types.