What does << mean in Javascript

 

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  • What do “>>” and “<<” mean in Javascript? 10 answers
  • What are bitwise shift (bit-shift) operators and how do they work? 8 answers
  • what does << do in javascript [duplicate] 2 answers

    • It's the bitwise left shift operator. The operands are converted to 32-bit integers, the left operand's bits are shifted left by the number of positions defined by the right operand, and the expression's value is the result.

    Here's a simple example: 

    var a = 1;
var b = a << 2; // Move the bit left by two places
console.log(b); // "4"

    That works because in a signed 32-bit integer, 1 looks like this in binary: 

    00000001

    If you move that bit to the left two places: 

    00000100

    ...you get 4 .

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