An address that points to (is the address of) a multi-byte object is the address to the first byte of that object – the byte that has the lowest address. As an aside, one important thing to note is that you can’t tell what the type of an object is - or even its size - by its address. In fact, you can’t even tell what type an object is by looking at it. An assembly language program needs to keep track of which memory addresses hold which objects, and how big those objects are. A program that does so is "type safe" because it only does things to objects that are safe to do on their type. A program that doesn’t will probably not work properly. Note that most programs do not actually explicitly store what the type of an object is, they just access objects consistently - the same object is always treated as the same type.