Sean O’Keefe, a data scientist at Google, on Thursday shared how Google thinks about their own internal SEO efforts for the 7,000 websites they manage. O’Keefe said Google makes on average over 200 changes to these sites on a daily basis and managing the SEO for those changes can be complex.

It’s a rare glimpse inside Google’s own SEO practices.

Small changes make a big impact. Google’s first point is that often with large sites, making small changes can make a big impact and return when it comes to search rankings. Google plotted the growth of one of the 7,000 websites, the Google My Business marketing site, showing how adding canonicals, hreflang to their XML sitemaps, and improving their metadata all resulted in gains in their organic traffic in search.