400 The Plain Http Request Was Sent To Https Port

The plain http request sent to https port is different from the original http request. here are some key differences:

ssl encryption is used in https protocol, which provides secure data transmission.
the use of ssl certificates allows for authentication and verification of the server's identity.
https requests require a valid ssl certificate to be sent with each request, while http requests do not.

here are some examples of websites that support https protocol:

example 1: youtube

        <https>://www.youtube.com

        <https>://paypal.sentryapp.com

conversely, some websites use http protocol for security reasons. here are a few examples:

        <http>://www.facebook.com

in this example, the request is sent to http port instead of https port. this may be due to compatibility or performance reasons.