Peter,
Getmemory(n) returns a pointer (address) to a memory block filled with null bytes. It is Typed as a sys integer, So you can do whatever you want with it.
There is another function News(n) and its synonym Nuls(n) which does exactly the same thing except it is treated as a Bstring so that string variables can receive it as an allocation of string space.
The traditional Space(n) and String(n,c) functions are also very closely related.
Charles