What are the differences between handling arrays in PHP and JavaScript, and how can they be effectively converted for use in both languages?

Handling arrays in PHP and JavaScript differs in syntax and some functionalities. To effectively convert arrays for use in both languages, you can use JSON encoding and decoding functions. In PHP, you can use `json_encode()` to convert an array to a JSON string, and `json_decode()` to convert a JSON string to an array. In JavaScript, you can use `JSON.stringify()` to convert an array to a JSON string, and `JSON.parse()` to convert a JSON string to an array.

// Convert PHP array to JSON string
$phpArray = array("apple", "banana", "cherry");
$jsonString = json_encode($phpArray);

// Convert JSON string to PHP array
$decodedArray = json_decode($jsonString);

// Accessing elements in the decoded array
echo $decodedArray[0]; // Output: apple