One of the strengths of the C language is that it allows you to use pointers to directly access memory locations.
Every Microsoft C program has at least two parts: the code (function definitions) and the data (variables and constants). As a program runs, it refers to elements of the code or the data by their addresses. These addresses can be stored in pointer variables.
Pointer variables can fit into 16 bits or 32 bits, depending on the distance of the object to which they refer.