I'm not sure what is meant by the main marketing activity going from "links and algorithms" to "shares and people". In 2000s, a lot of time was spent on gettin

I'm not sure what is meant by the main marketing activity going from "links and algorithms" to "shares and people". In 2000s, a lot of time was spent on getting people to give you links back to your site - PR teams generating content, viral/guerrilla marketing that people posted on their blogs, etc. In 2010s, understanding the algorithms that decide when to show what content to whom is essential. If you just buy a load of advertising on social media and hope that people see it, like it and share it, you're going to burn through a lot of money very quickly. It sounds great to say "wow, we're going through another revolution!" but in reality, social media is just another channel that sits alongside search. For me, the biggest change is how we share stuff: * Private to public - we used to share stuff either offline, or through email, with a small select group of people. Now we typically share things on Facebook or Twitter, where it's either completely public, or with a large group of people that we barely know. * Unstructured to structured - we used to share 'stuff'. Maybe it was a picture of my son, maybe a set of funny picture of cats, or an urban legend about some guy dying in a bath. Maybe the recipients were my colleagues, my family, my friends from university - the platform had very little idea. Now the content that we share is analysed in detail. The platform can be precise about the nature of the content, who it's shared with (and who reads it and then re-shares it). * Distributed to centralised - rather than millions of independent Wordpress, PHPBB and email servers, we now predominantly use a few platforms - Facebook, Twitter (plus a few smaller ones like Reddit, Hacker News). For me, those are the biggest changes. And now that much of our lives are public, centralised and structured, it's fairly easy to sell targeted advertising in a way that would either have been impossible or ineffective 10 years ago.