URL encoding converts characters into a format that can be sent through the internet. We should use URL encode for all GET parameters because POST parameters are automatically encoded.
URLs often contain characters outside the ASCII set, the URL has to be converted into a valid ASCII format. URLs use some characters for a special use in defining their syntax, when these characters are not used in their special role inside a URL, they need to be encoded. URL encoding is done to encode user input.
Example:
GEThttps://control.msg91.com/api/sendhttp.php?authkey=YourAuthKey&mobiles=9999999999&message=test & new&mobile&sender=123456&route=default
In this API, the message content "test & new" includes '&' operator, due to which URL encoding is necessary, otherwise it will break your message content and an incomplete message will be sent