Bitwise shifting and operators in Swift

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A bit is the smallest piece of information that can be 1 or 0 (on/off). Eight bits together are called a byte. A UInt8 in Swift is represented by 8 bits. The difference of this unsigned integer with the signed integer Int8 is that Int8 uses 1 bit to signify whether the integer is positive or negative. Having eight bits to represent a number means we can represent 2⁸ = 256 different numbers with UInt8.

0 = 00000000    2 = 00000010    4 = 00000100      8 = 00001000       
1 = 00000001    3 = 00000011    5 = 00000101      9 = 00001001
                                6 = 00000110     10 = 00001010
                                7 = 00000111     11 = 00001011
                                                 12 = 00001100
                                                 13 = 00001101
                                                 14 = 00001110
                                                 15 = 00001111
                                                 ...
                                                 255 = 11111111

Bitwise shifting

This is easiest explained with an example: say we have the number 8 represented by 00001000 and we do a left shift <<. This means that all bits will move one place to the left by removing the left bit and insert a new bit with the value 0 at the right. This will end up in number 16…