Http is most commonly used to access html pages, and it is important to consider that other resources can be utilized through accessing http. This was the way that most websites who did not house confidential information (such as credit card information) would setup their websites.
HTTPS, or “secure http”, was developed to allow authorization and secured transactions. Exchanging confidential information needs to be secured in order to prevent unauthorized access, and https makes this happen. In many ways, https is identical to http because it follows the same basic protocols. The http or https client, such as a Web browser, establishes a connection to a server on a standard port. However, https offers an extra layer of security because it uses SSL to move data.