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      Constants

      JavaScript Tutorial

      This JavaScript tutorial is crafted for beginners to introduce them to the basics and advanced concepts of JavaScript. By the end of this guide, you'll reach a proficiency level that sets the stage for further growth. Aimed at empowering you to progress towards becoming a world-class software developer, this tutorial paves the way for a successful career in web development and beyond.

      Constants

      JavaScript Constants

      In JavaScript, a constant is a variable that cannot be reassigned or redeclared once it has been initialized. This means that the value of a constant remains fixed throughout the program.
      
      To declare a constant in JavaScript, you use the const keyword followed by the name of the constant and its initial value. For example:
      const x = 10; // Correct Way
      In any case, you can't declare the variables with the const keyword without initialization.
      const y; // Incorrect way
      y = 20;

      Can't be Reassigned

      You can't update the value of the variables declared with the const keyword.
      const y = 20; 
      y = 40; // This is not possible

      Block Scope

      A JavaScript variable declared with const keyword has block-scope. This means same variable is treated as different outside the blcok.
      In the below example, the x declared within block is different from x declared outside the blcok. So we can redeclare the same variable outsite the block
      {
      const x = "john";
      }
      const x = "Doe"
      But we can't redeclare the const varaible within the same block.
      {
      const x = "john";
      const x = "Doe" // incorrect
      }