When a web browser sends a POST request from a web form element, the default Internet media type is “application/x-www-form-urlencoded”.[8] This is a format for encoding key-value pairs with possibly duplicate keys. Each key-value pair is separated by an ‘&’ character, and each key is separated from its value by an ‘=’ character. Keys and values are both escaped by replacing spaces with the ‘+’ character and then using URL encoding on all other non-alphanumeric[9] characters.