The positions (from left to right) correspond to powers of two: (2^{15}) down to (2^0). Only bits at positions (2^{14}) and (2^1) are set to 1 (since the string has a 1 in the second position and another 1 in the second-to-last position). Thus:

0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0

So, as a pure binary number, 0100000000010000 equals the decimal integer . 2. A Glimpse into Computer Architecture This number, 16386, is not random either. It sits precisely one above 16385, which is (2^{14} + 1). But more interestingly, consider if this 16-bit string were not data, but an instruction in a simple processor’s instruction set architecture (ISA). In many early 16-bit CPUs (like the PDP-11 or the 6502 with 16-bit addressing), the first few bits of an instruction denote the opcode, and the rest specify registers or memory addresses.