How Google's Rankings Algorithm Has Changed Over Time

Rand in his blog has clearly represented the algorithm changes of Google over the past few years in a graph. This clearly shows the trends that happened over the years. It is a great way to communicate the changes with this small graph which says all. As it is said – pictures tell a thousand words.

According to Rand, Domain Trust/Authority is playing lot of role in SERPs. My question here is how does Google measure the website’s domain authority? I guess an authority domain is generally one with large number of pages, is popular with more visitors, has lots of inbound links, its content is frequently updated and re-indexed. This means to achieve domain authority, you need to do the other SEO techniques mentioned in the graph as well. All other techniques lead to domain authority.

And I guess no one exactly knows how or at what stage a domain or website acquires authority. If an article is published in such authority website, it will generally start ranking for its keywords relatively very fast compared to something similar published in a non-authority domain. So it boils down to what matters is where the content or link is published rather than what it is.