All websites have HTTP pages, and then some have HTTPS pages with the same exact content on them. This usually occurs because many websites like to offer certain types of content on HTTP pages instead of HTTPS pages because of the slight performance degradation offered by HTTPS pages. But the website still wants the option of being able to use secure pages when necessary, which is why they have both HTTP and HTTPS pages.
Google has been doing a lot of thinking about Internet security lately, and has been dropping hints that it may start to favor HTTPS pages. To get ahead of any type of action by Google, most social media pages switched to HTTPS pages to offer better security. But now other websites may want to consider using HTTPS pages for more than just their ecommerce pages if they want to bring in traffic.
Google wouldn't have to make these changes if every website simply used HTTPS pages instead of unsecured HTTP pages. There are two reasons why websites try to use HTTP pages as much as possible in lieu of HTTPS pages. The first is that websites cannot be cached with HTTPS pages, and that can affect international web traffic. A web server that is on a different continent from the user will take much longer to access with HTTPS pages because the user's browser is not allowed to cache the site.
The other reason websites attempt to bypass using HTTPS pages is the slower loading times. Retail websites know that every millisecond of website lag means the loss of more revenue, and they would rather not slow their sites down. But as the need for security increases, most of the major retail websites have turned all of their pages into HTTPS pages.
If Google sees that you have an HTTP page that has the same identical content as an HTTPS page, then it is going to index the HTTPS page first. But, as with any rule, there are exceptions. Google will not index the HTTPS page first if it:
In these instances, Google will index the HTTP page first, and it may not index the HTTPS page at all.
Website owners should pay attention whenever Google says it will favor one type of web page over another for any reason. If you have a site that is utilizing all HTTPS pages and your site has a valid security certificate, then you could find your site ranked ahead of the competition. Google is being vague on details right now, so understanding the exact effects of this are difficult.
The best approach is to team up with an experienced Internet marketing company and have them evaluate your website for you. If there is an advantage to making all of your pages HTTPS pages, then your marketing expert can make that call for you. As Google continues to alter the search landscape, you need a professional organization that can keep up with the changes and keep your company competitive.