Arrow Functions

When using an arrow function with a single parameter, the parentheses around the parameter are optional. For example, both `x => x * 2` and `(x) => x * 2` are valid and equivalent. This is a syntactic convenience that makes arrow functions even more concise for the common case of single-parameter functions. However, parentheses are required in all other cases: when there are no parameters (`() => result`), multiple parameters (`(x, y) => x + y`), or default parameters (`(x = 1) => x * 2`). Also, curly braces are optional for the function body only when there's a single expression that you want to implicitly return. For multi-statement function bodies, curly braces are required, and an explicit `return` statement is needed to return a value. This flexibility in syntax allows developers to write very concise functions for simple operations while still supporting more complex implementations when needed.