Keeping track of and allocating storage that is needed during the execution of a program is called dynamic storage management. In some languages, notably FORTRAN, storage for arrays is allocated before the program's execution, and no dynamic storage management is present. In languages like C, storage is allocated to the local variables of a function at the start of its execution and remains assigned until the function (or block) completes its execution. The space can then be reassigned to the next executing function (or block). In effect, it disappears. This is why values of local variables are not preserved between invocations of a function, unless they are declared as static, in which case they are preserved between calls. Management of this storage during the execution of a program is not what is meant by dynamic storage management. Contrast this situation to dynamic memory, which is assigned or taken away from records in dynamic memory during the execution of a function itself. This captures the true flavor of dynamic storage allocation.
If the array in which records are to be kept (as in Sections 3.6.2 and 3.6.3) is to function as dynamic memory, then allocating storage in the array for a record requires dynamic storage management. In fact, this amounts to an implementation of a C-like dynamic memory. Although storage can thus be managed explicitly for a specific program, dynamic memory can manage storage for many programs and is hence more efficient use of storage. The difference is that one large array may function as storage to be used by all the programs, instead of dedicating separate smaller arrays to each program.