In the first half of this year, there has been a lot of SEO-related news coming out from Google. Google has pushed out many new algorithms, made many changes to the search result interfaces, penalized many websites and tactics, as well as sent out many warnings about upcoming penalties or actions.

All of this was covered in depth on our sister site, Search Engine Land, but a recap is in order for our Marketing Land readers.

Below, I will summarize the changes in order of Google’s Panda algorithm, Penguin algorithm, and other algorithm updates and launches. I will then discuss some of the manual actions taken and then some of Google’s warnings and statements.

Google Panda Algorithm

Google’s Panda algorithm launched in February 2011 and has since been at the top of the minds of webmasters and SEOs. In the past six months, we learned a lot about Panda. Google recently started to roll out Panda updates over a 10 day period and promised to not give us confirmations of Panda updates going forward. Below are some of the stories we covered in the past six months on this content hungry algorithm.

Google Penguin Algorithm

Google’s Penguin algorithm launched in April 2012, and while Panda looked closely at content, Penguin went after links pointing to a page. While Panda’s algorithm impacted a larger percentage of the search results, i.e., 12%, the Penguin update was probably felt more by SEOs, but only impacted about 3% of the search results. We counted four updates to the algorithm since its launch, but in 2013, Google significantly updated the algorithm calling it Penguin version 2.0.

The previous updates happened as such:

Penguin 1 on April 24, 2012 (impacting ~3.1% of queries)

Penguin 2 on May 26, 2012 (impacting less than 0.1%)

Penguin 3 on October 5, 2012 (impacting ~0.3% of queries)

Penguin 4 on May 22, 2013 (impacting 2.3% of queries)

Other Google Algorithm Updates/Launches

Outside of the big guns, Penguin and Panda, we had many other algorithm and launches from Google in the past six months. From the PayDay loan algorithm, to mobile site speed and domain clustering – Google has been busy working on improving their relevancy and combating spammers. Here are some of the major changes to the algorithm in the past six months.

Google’s Manual Actions:

Algorithms, such as those mentioned above, impact a wider base of sites, but Google also has an army of search quality analysts that patrol the Web to find sites manipulating their search results and getting by the algorithm. There is a difference between algorithm and manual penalties, and below are some of the manual actions Google has taken or promised to take in the past six months. Some of these impacted huge brands, while others impacted specific industries or techniques.

Google SEO Advice & Statements

Google has commonly given advice to the webmaster and SEO community over the years. Some of these come in the form of videos, blog posts and messages conveyed at search conferences. Below is a list of some of the more important tips and words of advice from Google in the past six months.