A 64-bit programming model in which longs and pointers are both 64 bits in length. Other standard
C data types are shorter. Below is a table of sizes
(in bits) for the standard C data types:
Type Size
char 8
short 16
int 32
long 64
pointer 64
Having 32-bit integers makes it easier to have 32 bit programs coexist with 64 bit programs all in the same system.