Google is the world's most popular website. It also happens to be society's most authoritative search engine. Google - the company, not the search engine - regularly engages in countless other tech-related activities such as maintaining Google AdWords and Gmail.
Technicians at Google who are responsible for maintaining the almighty algorithm - the "formula," more or less, that's used for ranking web pages - regularly publish updates to it for several reasons.
All considered, and without going into detail at all, the reason why Google changes its algorithm is to provide a better experience for everybody who uses the search engine. These changes also eliminate any and all exploits that black-hat search engine optimizers discover; this also improves the experiences of all users.
When did Google most recently make changes to the search engine's algorithm?
Keep in mind that Google is not required to tell the general public or its clients about the modifications the company makes to its algorithm. Further, they often make small changes on a regular basis without actually telling anybody.
However, Google will pile up necessary fixes that need to be implemented within the algorithm for the sake of simplicity. Such piles of stuff, once they've been taken care of, are usually acknowledged by Google itself, as a company, or other authoritative sites such as Search Engine Roundtable.
Anyways, the last time that the Google search engine algorithm was updated was Nov. 8, 2019.
People aren't too happy about these most recent changes
When Google messes with the existing version of the algorithm, people are bound to complain about how their websites have dropped in search engine results page rankings. However, this time around, people across Twitter, SEO-related forums, and elsewhere on the Internet have been going absolutely crazy over the past few days.
Now that these changes have been in place for about a week now, you will be able to more readily come across tried-and-true website adaptations others have carried out in order to level out the effects of this change. For more information click here https://www.reddit.com/r/SEO/comments/dw3ciu/unconfirmednovembergoogleupdatefinally/.