Here are some of the core changes in SEO that Google made in 2018: Read more at searchengineland.com
1. Mobile First indexing - implemented mobile first indexing to ensure that there is a separate index for mobile devices. This meant that the SEOs need to optimise separately for mobile devices and ensure that the websites are mobile optimised first.
2. Speed Update - Google implemented an update that ensured that Page Speed will become a ranking factor for Google in mobile search. It encouraged websites to implement AMP pages so that the mobile websites are accelerated.
3. Structured data - Google laid more focus on structured data to improve the search results. It launched 'Speakable markup' for voice search related queries, enabled a job indexing API for job search queries, launched Q&A and FAQ schemas and more.
4. Search Console - Google updated the search console and made several changes to the tools inside the console. It removed the public URL submission tool, changed limits and quotas for indexing an URL, and started sending out slow site notices to webmasters.
5. Google My Business and Posts - Google launched Google posts, a way to create content that gets prioritised on Google Search. Google updated the GMB control panel and added a lot of analytics and features so that we can manage our accounts on the go.
6. Google Home and Assistant - Google made few changes to both and these are looked at by the SEO community as being a big way to get access to queries and users.