5.5.2 Explicit Data Typing
  BASIC provides the following declarative statements. These
  statements create variables and allocate storage.

        DECLARE
        DIMENSION
        COMMON
        MAP

  The statement you choose depends on the way in which you
  will use the variables:

  .
        DECLARE and DIMENSION allocate dynamic stor-
        age for variables; storage is allocated when the program
        executes.
  .
        COMMON and MAP statements allocate storage for
        variables statically; storage is allocated when the program
        is compiled.

  All declarative statements assocaite a data type with a vari-
  able. For more information, see Chapter 8.