1.7 The Memory Subsystem
A typical 80x86 processor running a modern 32-bit OS can access a maximum of 232 different memory locations, or just over 4 billion bytes. A few years ago, 4 gigabytes of memory would have seemed like infinity; modern machines, however, exceed this limit. Nevertheless, because the 80x86 architecture supports a maximum 4GB address space when using a 32-bit operating system like Windows, Mac OS X, FreeBSD, or Linux, the following discussion will assume the 4GB limit.
Of course, the first question you should ask is, "What exactly is a memory location?" The 80x86 supports byte-addressable memory. Therefore, the basic memory unit is a byte, which is sufficient to hold a single character or a (very) small integer value (we'll ...
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