👉 The `let` keyword in JavaScript is a static keyword introduced in ECMAScript 2022, designed to optimize the performance of template literals and string interpolation. When used in a template literal, `let` allows for the creation of variables within the string that retain their values across multiple interpolations, unlike traditional string concatenation or template literals without `let`. This means that variables defined within a template literal using `let` are preserved and can be referenced multiple times without re-declaring them, improving readability and efficiency. For example, `const name = 'Alice'; let message = `Hello, ${name}!`;` will correctly assign the value of `name` to `message` even after subsequent interpolations, unlike a simple string concatenation which would result in `Hello, undefined!`.
