The preferred domain or sometimes also referred as the canonical domain is the one that you would like to be used to index your site’s pages. Links may point to your site using both the www.domain.com and domain.com. The preferred domain is the one you want to show up in search results. This decision is based on many factors, s.a. how sites load in google search results -index analysis and how sites are linked to other people-link analysis, using f.e. Alexa, Majestic.com, etc.
Once you set with your choice, you’ll need to let Google know which site you would like to use for future crawls of your site and indexing refreshes and to set it up your preferred domain by using Google Web Master tools.
If you have any questions or need assistance with setting up your preferred domain or any SEO digital media marketing services, please contact DigiBizMarketing LLC