Variables: let, const & var — Free JavaScript Tutorial
Learn Variables: let, const & var in JavaScript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
TL;DR: Learn Variables: let, const & var in JavaScript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
Variables: let, const & var in JavaScript
`var` is the old way to declare variables — it is function-scoped and hoisted (moved to the top internally). Avoid `var` in modern code.
`let` is block-scoped. It can be reassigned but not re-declared in the same scope. Use `let` for values that change.
`const` is block-scoped. It CANNOT be reassigned. Use `const` by default — change to `let` only when needed. `const` for objects/arrays doesn't make the contents immutable, just the binding.
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