What does << means in javascript

 

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  • What are bitwise shift (bit-shift) operators and how do they work? 8 answers

    • It means bitwise left shift. Same as it means in most other programming languages.

    Some console test: 

    >a = 2
2
>a << 1 
4
>a << 3
16

    It's the bitwise left operator. In a << b , it shifts a in binary representation b (< 32) bits to the left, shifting in zeros from the right.

    Some examples: 

    a = 1       // 00000001 in binary
b = a << 1  // equals to 2, 00000010 in binary
c = a << 2  // equals to 4, 00000100 in binary

document.write('a << 1 = ' + b + '<br />'
               + 'a << 2 = ' + c);
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