Google’s algorithms are a complex system used to retrieve data from its search index and instantly deliver the best possible results for a query. The search engine uses a combination of algorithms and numerous ranking signals to deliver webpages ranked by relevance on its search engine results pages (SERPs).
In its early years, Google only made a handful of updates to its algorithms. Now, Google makes thousands of changes every year.
Most of these updates are so slight that they go completely unnoticed. However, on occasion, the search engine rolls out major algorithmic updates that significantly impact the SERPs such as:
- Intrusive Interstitials Update
- EMD (Exact Match Domain)
- Page Layout Algorithm
May 2020 Core Update
Google Search Liaison Danny Sullivan announced via Twitter that Google would be releasing a broad core algorithm update. About 90 minutes later, he announced the update was underway and would take 1-2 weeks to completely roll out.
(source: Search Engine General)