No, they usually mean something. At the lowest levels of code, people have often used variables composed of bit-maps where each bit means something. Then you can construct a value that is a combination of bits (flags) and test for multiple items at once. An example would be the bit flags used in disk access calls. One bit flag means read, another write, another means from the beginning, another means from the end, another lock the file while we're using it. Using the made-up example below, you can then write a conditional statement like:
if append then (move the pointer to the end of the file)
1:
2:
3:
4:
5:
6:
7:
8:
9:
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// made-up bit definitions
read = 1 ;bit 1
write = 2 ;bit 2
beginning = 4 ;bit 3
end = 8 ;bit 4
lock = 16; bit 5
// so write at the end (append) would be:
append = 10 ;bits 2 and bit 4 = 2+8
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