To show MLS data on a real estate website, MLS Integration needs to be deployed. There are quite a number of IDX and RETS providers, each with different technology and pricing. After the integration, the end result may look similar, but the underlying technology plays an important role in the popularity of your website, especially from the search engine point of view.
Organic MLS is a method of MLS integration that brings search engine value to your website by inserting the MLS properties directly to your website database. For search engines it is very important to read the properties directly from your database, rather than through a third party database ( MLS/IDX Provider).
In Organic MLS integration, metaphorically the downloaded properties (from MLS to your website) become like the living organs of your own website. As a result, the search engines will consider your website as an informative website with hundreds of URLs to index.