cons and let keywords

1. const and let both are the keywords for variable declaration.

2. const and let both are the block scope.

### Block Scope Example

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      const blockVariableExample = () => {

            let number = 123;

            console.log(number) // Prints 123

       }

       

       blockVariableExample;

       console.log(number) // Here it gives error as number varaible can only be accessed inside blockVariableExample function

1. const cannot be redeclared or updated while we can redeclare let variables.

   const Example

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     const number = 123
   
         
   
     // Updating a const variable
   
     number = 324 // Gives error assignment to const variable
   
         
   
     // Redeclaring a const variable
   
     const number = 567 // Gives error identifier number has already been declared
   
   

   let Example

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     let number = 123
   
         
   
     // Updating a let variable
   
     number = 324 // It updates the variable number to 324
   
         
   
     // Redeclaring a let variable
   
     let number = 567 // Gives error identifier number has already been declared