In JavaScript, variables are like containers that store data. There are three ways to create (or declare) these containers: var, let, and const. 
Letβs look at what makes them different! π
- 
varβ The Old-School Way π
Scope: var works within the function it's declared in (function-scoped), so it can be used anywhere inside that function. π
Hoisting: JavaScript "hoists" or moves var declarations to the top of the function, but only the declaration, not the value. 
This can sometimes cause confusion. π
Example:
var name = "Alice"; // Variable declared with 'var'
- 
letβ The New Standard π±
Scope: let is block-scoped, which means it's only available inside the block (curly braces {}) where itβs declared. 
This makes it more predictable. π§±
Reassignable: You can change the value of a let variable if needed. π
Example:
let age = 25; // Variable declared with 'let'
age = 30;   // You can reassign it
- 
constβ The Permanent One π
- Scope: Like - let,- constis also block-scoped. βοΈ
- Non-Reassignable: Once a value is assigned to a - constvariable, it can't be changed. This is used when you donβt want the value to change. β
Example:
const birthYear = 1995; // Variable declared with 'const'
birthYear = 2000; // Error! You can't change it
When to Use Them:
Use let when you need to update the variableβs value later.
Use const when the value should stay the same (like a constant).
Avoid var in modern JavaScript because let and const are more reliable.
By understanding let, const, and var, you'll write cleaner, more predictable JavaScript! π―
 

 
    
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