Google Algorithm History
The web today is full of thousands, if not millions of web pages, offering helpful information about almost everything that you would like to know about. In such a scenario, search engine’s like Google make use of algorithms, that are computer programs and formulas that work on taking your search questions and providing you useful answers with links to web pages that contain the exact information that you want.
Google algorithms rely on over 200 unique signals including things like the terms on websites, the freshness of content, your region and PageRank to make it possible to guess what you might really be looking for.
Google keeps making changes to its search algorithms regularly. While most of the changes are minor ones, Google also rolls out major algorithm updates from time to time that affect its search results significantly. Today we are going to talk about Google Algorithm Change History mentioning all the major algorithmic changes that have made huge impact on Google searches.
2016 updates
1- Unnamed update – 8th January: Google confirmed a core search ranking update took place when multiple tracking tools including MozCast reported historically-large rankings movement. Google also announced officially that this update wasn’t Penguin related.
2015 updates
1- RankBrain – 26th October: Google revealed that machine learning had been a part of the algorithm for months, turning Google’s lucrative web search over to AI machines. It has contributed to the 3rd most influential ranking factor.
2- Panda 4.2 (#28) – 17th July 17: Google announced a Panda data refresh which would actually take months to roll out completely. No immediate impacts could be seen as the update very slowly rolled out.
3- The Quality update – 3rd May: Google acknowledged a core algorithm change impacting quality signals, leading to a lot many large-scale ranking changes. It seemed to have a broad impact and ended up punishing several low-quality sites as a side-effect.
4- Mobile update aka Mobilegeddon – 22nd April: Google announced this algorithm update which was to affect mobile rankings for mobile-friendly sites, starting on 21st April. However, the impact of this update came out to be much smaller than expected and the algorithm flux only peaked on 22ndApril. It helped in providing more mobile-friendly search results.
5- Unnamed update – 4th February: Several SERP-trackers and webmasters confirmed a major flux in Google SERPs, where speculation ranged from an e-commerce focused update to a mobile usability update. Though Google didn’t confirm an update but it was the Google Brand e-Commerce update which caused all fluctuations.
2014 updates
1- Pigeon Expands (UK, CA, AU) – 22nd December: Google’s local algorithm update ‘Pigeon’ had originally hit the United States in July 2014. And by December, it expanded to the United Kingdom, Canada and Australia. It was confirmed on the 22nd but it may have rolled out as early as the 19th.
2- Penguin Everflux – 10th December: Google said that Penguin made a shift to ‘continuous updates’, from infrequent, major updates. This claim exposed by a Google representative seemed to be real as it fit the then ongoing flux after Penguin 3.0, including unconfirmed claims of a Penguin 3.1.
3- Pirate 2.0 – 21st October: Over 2 years after the original DMCA/Pirate update, Google launched a highly targeted Pirate 2.0 update to combat software and digital media piracy which caused dramatic drops in ranking to a relatively small group of sites. It is reported to have hit the torrent sites hard.
4- Penguin 3.0 – 17th October: Over a year after the Penguin update (2.1), Google launched another Penguin refresh, which seemed to be smaller than expected (<1% of US/English queries affected). It was probably data-only. Google claimed that the update was spread over ‘weeks’ because of which the timing of the update was unclear, especially internationally.
5- In The News Box – October: Google made a change to News box results. It appeared as if it is a display change but they later announced that the expansion of news links to a much larger set of potential sites from the traditional news sites. This resulted in substantial traffic changes to major news sites.
6- Panda 4.1 (#27) – 23rd September: A significant Panda update was announced. With the slow rollout of Google’s 27th Panda update, the exact timing was unclear and it had an expected impact of 3-5% to queries.
7- Authorship Removed – 28th August: After the 28th June drop of authorship photos, Google announced to completely remove authorship markup. And by the next morning, authorship bylines had disappeared from all SERPs. The official announcement came from john Mueller.
8- HTTPS/SSL update – 6th August: Google announced to give preference to secure site which meant that adding encryption would provide a little boost to rankings. Google stressed that this boost to secure HTTPS/SSL sites would start out small, but implied to increase it if the change proved to be positive.
9- Pigeon – 24th July: Google claimed that Pigeon created closer ties between the local algorithm and core algorithm, which dramatically altered some local results, shaking the local SEO world.
10- Authorship Photo Drop – 28th June: John Mueller announced on 25th June that Google would be dropping all authorship photos from SERPs. This drop was complete around 28th June.
11- Payday Loan 3.0 – 12th June: Less than a month after the Payday Loan 2.0 anti-spam update, Google launched 3.0, which targeted spammy queries.
12- Panda 4.0 (#26) – 19th May: Google confirmed a major Panda update which probably included both an algorithm update and a data refresh. It officially affected about 7.5% of English-language queries.
13- Payday Loan 2.0 – 16th May: Google updated its Payday Loan algorithm targeting spammy queries. The exact date of the roll-out was unclear and the back-to-back updates made it difficult to sort out the details.
14- Unnamed update – 24th March: Some major algorithm flux trackers and webmaster chatter speculated that the new, softer, Panda update had arrived around 24th-25th. Many sites reported ranking changes. However, Google never confirmed this update.
15- Page Layout #3 – 6th February: Google refreshed their page layout algorithm, which was originally launched in January 2012. It penalizes sites with too many ads above the fold.
2013 updates
1- Authorship Shake-up – 19th December: Authorship mark-up disappeared from roughly 15% of queries over a period of about a month. The fall bottomed out around December 19th.
2- Unnamed update – 17th December: Almost all global flux trackers registered historically high activity. MozCast also registered a rise in some Partial-Match Domains (PMDs). But Google denies a major update, saying that they avoid updates near the holidays.
3- Unnamed update – 14th November: Several Google trackers picked up unusual activity along with a report of widespread DNS errors in Google Webmaster Tools. The cause and nature of this flux was unclear since Google did not confirm an update.
4- Penguin 2.1 (#5) – 4th October: After a gap of 4-1/2 months, Google launched another Penguin update, which was probably a data update (primarily) with no major change to the Penguin algorithm. The overall impact of this update seemed to be moderate, although some webmasters reported being hit hard.
5- Hummingbird – 20th August: This update was announced on 26th September. However, Google suggested that the update rolled out about a month earlier. Many reports of flux were registered around 20th-22nd August including a MozCast spike on 20th August. Hummingbird seems to be a core algorithm update affecting semantic search and the Knowledge Graph for months to come.
6- In-depth Articles – 6th August: Google added a new type of news result called in-depth articles, which was dedicated to more evergreen, long-form content. When launched, it included links to three articles and appeared across about 3% of the searches that MozCast tracks.
7- Unnamed Update — 26th July: MozCast tracked a large Friday spike (105° F) along with other sources showing significant activity over the weekend. Google has not confirmed this update.
8- Knowledge Graph Expansion — 19th July: Queries with Knowledge Graph (KG) entries expanded by more than half (+50.4%) across the MozCast data set.
9- Panda Recovery – 18th July: Google confirmed a Panda update. This was probably an algorithmic update, which might have softened some previous Panda penalties.
10- Multi-Week update – 27th June: Google’s Matt Cutts’ tweet suggested a multi-week algorithm update around 4th-12th June. The nature of the update was unclear, but there was massive rankings volatility during that time period, which peaked on 27th June 27th according to MozCast data.
11- Payday Loan update – 11th June: Google announced a targeted algorithm update to take on niches with notoriously spammy results such as payday loans and porn. The update was announced on 11th June but Matt Cutts suggested it would roll out over a 1-2 month period.
12- Panda Dance – 11th June: While not an actual Panda update, it suggested that Panda was still updating monthly with each update rolling out over about 10 days.
13- Penguin 2.0 (#4) – 22nd May: The 4th Penguin update, which was more finely targeted to the page level, arrived with only moderate impact.
14- Domain Crowding – 21st May: Google released an update to control domain crowding/diversity deep in the SERPs (pages 2+). The timing was unclear but it had possibly rolled out just prior to Penguin 2.0 in the US and possibly the same day internationally.
15- Phantom – 9th May: There were many reports of an algorithm update with several sites reporting significant traffic loss.
16- Panda #25 – 14th March: The exact date of the update was unconfirmed, but MozCast data suggests 13th-14th.
17- Panda #24 – 22nd January: Google announced its first official update of 2013, claiming 1.2% of queries affected. This was the 24th Panda Refresh and was not related to 17th January.
2012 updates
1- Panda #23 – 21st December: Right before the Christmas holiday, Google rolled out another Panda update, officially calling it ‘Refresh’. It impacted 1.3% of English queries, which was a slightly higher impact than Pandas #21 and #22.
2- Knowledge Graph Expansion – 4th December: Google added Knowledge Graph functionality to non-English queries, including Spanish, French, German, Portuguese, Japanese, Russian and Italian. This update added enhanced KG capabilities.
3- Panda #22 – 21st November: Google confirmed the 22nd Panda update, which seemed to have been a data-only update. It impacted 0.8% of queries.
4- Panda #21 – 5th November: Google rolled out their 21st Panda update, roughly 5-1/2 weeks after Panda #20. This update officially impacted 1.1% of English queries.
5- Page Layout #2 – 9th October: Google announced an update to its original page layout algorithm change back in January, which targeted pages with too many ads above the fold. It is unclear if this was an algorithm change or a Panda-style data refresh.
6- Penguin #3 — 5th October: Google released a minor Penguin data update, impacting 0.3% of queries. This was the 3rd Penguin release.
7- August/September 65-Pack – 4th October: Google published their monthly/bi-monthly list of search highlights. The 65 updates for August and September included 7-result SERPs, Knowledge Graph expansion, updates to how page quality is calculated and changes to how local results are determined.
8- Panda #20 — 27th September: This was a fairly major Panda update, both algorithm update and data update, officially affecting 2.4% of queries.
9- Exact-Match Domain (EMD) Update — 27th September: Google announced a change in the way it was handling exact-match domains (EMDs), which led to large-scale devaluation. It reduced the presence of EMDs in the MozCast data set by over 10%, impacting 0.6% of queries.
10- Panda 3.9.2 (#19) — 18th September: Google rolled out another Panda refresh, which appears to have been data-only. It caused a moderate ranking flux.
11- Panda 3.9.1 (#18) — 20th August: Google confirmed yet another Panda data update with a fairly small impact.
12- 7-Result SERPs – 14th August: Google made a significant change to the Top 10, limiting it to 7 results for many queries. This change rolled out over a couple of days, finally impacting about 18% of the keywords we tracked.
13- June/July 86-Pack — 10th August: The June and July Search Quality Highlights were rolled out in one mega-post including Panda data and algorithm refreshes, an improved rank-ordering function, a ranking boost for trusted sources and changes to site clustering.
14- DMCA Penalty (“Pirate”) — 10th August 10: Google announced to start with penalizing sites which repeat copyright violations, probably via DMCA takedown requests. Timing was stated as starting next week from 8th.
15- Panda 3.9 (#17) — 24th July: Google rolled out a new Panda update, one month after Panda 3.8. Rankings fluctuated for 5-6 days, although no single day was high enough to stand out. A less than 1% of queries were impacted.
16- Link Warnings — 19th July: Google sent out a large number of unnatural link warnings via Google Webmaster Tools and then says, that these new warnings may not actually represent a serious problem and you can ignore them.
17- Panda 3.8 (#16) – 25th June: Google rolled out another Panda data refresh, which seemed to be data only and had a much smaller impact than Panda 3.7.
18- Panda 3.7 (#15) – 8th June: Google rolled out yet another Panda data update, impacting less than 1% of queries. Ranking fluctuation data suggested that the impact was substantially higher than Panda 3.5 and Panda 3.6 updates.
19- May 39-Pack – 7th June: Google released their monthly Search Highlights with 39 updates in May including Penguin improvements, better link-scheme detection, changes to title/snippet rewriting and updates to Google News.
20- Penguin 1.1 (#2) – 25th May: Google rolled out its first targeted data update after the Penguin algorithm update.
21- Knowledge Graph – 16th May: Google started rolling out Knowledge Graph, a SERP-integrated display providing supplemental object about certain people, places and things. This update was to provide answers, not just links.
22- April 52-Pack – 4th May: Google published details of 52 updates in April, including changes tied to the Penguin update, a 15% larger base index, improved pagination handling and a number of updates to site links.
23- Panda 3.6 (#14) – 27th April: Google rolled out yet another Panda data update, just a week after Panda 3.5. Its implications were unclear and were relatively small.
24- Penguin – 24th April: Google rolled out the web spam update after weeks of speculation about an over-optimization penalty, which was dubbed Penguin. It adjusted a number of spam factors, including keyword stuffing. This update impacted an estimated 3.1% of English queries, rewarding high-quality sites.
25- Panda 3.5 (#13) – 19th April: Google rolled out a Panda data update, which appeared to be a fairly routine update with minimal impact.
26- Parked Domain Bug – 16th April: Many webmasters reported ranking shuffles. After this, Google confirmed that a data error had caused some domains to be mistakenly treated as parked domains.
27- March 50-Pack – 3rd April: Google posted another batch of update highlights, including confirmation of Panda 3.4, changes to anchor-text scoring, updates to image search and navigational search and changes to how queries with local intent are interpreted.
28- Panda 3.4 (#12) – 23rd March: Google announced another Panda update, which impacted about 1.6% of search results.
29- Search Quality Video – 12th March: Google published a rare peek into a search quality meeting. This wasn’t an algorithm update.
30- Venice – 27th February: As part of their monthly update, Google made this local update which brought in new ranking opportunities for Local SEO.
31- February 40-Pack (2) – 27th February: Google published a second set of search quality highlights, which included multiple image-search updates, multiple freshness updates and a Panda update.
32- Panda 3.3 (#11) – 27th February: Google rolled out another post-flux Panda update, which came just 3 days after the 1-year anniversary of Panda. It appeared to be a relatively minor one.
33- February 17-Pack – 3rd February: Google released another round of search quality highlights (17), many of which were related to speed, freshness and spell-checking. One major announcement was tighter integration of Panda into the main search index.
34- Ads Above The Fold — 19th January: Google updated their page layout algorithms to devalue sites with too much ad-space above the fold. The update had no official name.
35- Panda 3.2 (#10) – 18th January: Google confirmed a Panda data update.
36- Search + Your World — 10th January: Google announced a radical shift in personalization – aggressively pushing Google+ social data and user profiles into SERPs. Google also added a new, prominent toggle button to shut off personalization.
37- January 30-Pack — 5th January: Google announced 30 changes, including image search landing-page quality detection, more relevant site-links, more rich snippets and related-query improvements.
2011 Updates
1- December 10-Pack — December: Google outlined a second set of 10 updates, including related query refinements, parked domain detection, blog search freshness and image search freshness. The exact dates of each update were not provided.
2- Panda 3.1 (#9) — 18th November: Some industry analysts called it the 11/18 update 3.1, even though there was no official 3.0.
3- 10-Pack of Updates — 14th November 14: Google’s Matt Cutts released a post with 10 recent algorithm updates, most of which were small ones including improved snippets, rank boost, etc.
4- Freshness update – 3rd November: Google announced an algorithm change rewarding freshness, which would impact up to 35% of queries. This update primarily affected time-sensitive results, but signalled a much stronger focus on recent content.
5- Query Encryption – 18th October: Google announced that they would be encrypting search queries, for privacy reasons. This update was dedicated to making search more secure.
6- Panda Flux (#8) – 5th October: Matt Cutts tweeted that you can expect some Panda-related flux in the next few weeks, impacting a less than 2% of queries. Other minor Panda updates occurred on 3rdand 13th October and 18th November.
7- Panda 2.5 (#7) – 28th September: Google rolled out another Panda update with unclear details but some sites reported large-scale losses.
8- 516 Algo updates – 21st September: This wasn’t an update, but it was an amazing revelation where Google CEO Eric Schmidt told Congress that Google made 516 updates in 2010. And they tested over 13,000 updates.
9- Pagination Elements – 15th September: Google introduced the rel=”next” and rel=”prev” link attributes to help fix crawl and duplication problems created by pagination.
10- Expanded Site-links – 16th August: Google officially rolled out expanded site-links, which had 12-packs at first but Google appeared to limit the expanded site-links to 6 shortly after the roll-out.
11- Panda 2.4 (#6) – 12th August: Google rolled out Panda internationally, both for English-language queries globally and non-English queries except for Chinese, Japanese and Korean. This impacted 6-9% of queries in affected countries.
12- Panda 2.3 (#5) – 23rd July: Webmaster chatter suggested another update roll out by Google. It was unclear whether new factors were introduced or this was simply an update to the Panda data and ranking factors.
13- Google+ – 28th June: After a number of social media failures, Google launched a serious attack on Facebook with Google+. Google+ was tightly integrated into products like Gmail and within 2 weeks Google+ reached 10M users.
14- Panda 2.2 (#4) – 21st June: Google continued to update Panda-impacted sites and data, officially acknowledging its version 2.2.
15- Schema.org – 2nd June: Google, Yahoo and Microsoft united to jointly announce making search listings richer through structured data. They created a number of new schemas in an apparent bid.
16- Panda 2.1 (#3) – 9th May: Initially dubbed Panda 3.0, Google seemed to roll out yet another round of changes, which weren’t discussed in detail by Google. This Panda update 2.1, not Panda 3.0, seemed to be relatively minor.
17- Panda 2.0 (#2) – 11th April: Google rolled out a Panda update to all English queries worldwide. This Panda update incorporated searcher blocking data.
18- The +1 Button – 30th March: Google launched the +1 button in response to competition by major social sites like Facebook and Twitter. Clicking this +1 button allowed users to influence search results within their social circle, across both organic and paid results.
19- Panda/Farmer – 23rd February: This was a major algorithm update which hit sites really hard, impacting up to 12% of search results, as claimed Google. This update cracked down on thin content, content farms, sites with high ad-to-content ratios. It rolled out over at least a couple of months, hitting Europe in April 2011.
20- Attribution update – 28th January: Google rolled out this update to help better sort out content attribution and stop scrapers. This update affected about 2% of queries.
21- Overstock.com Penalty – January: Google penalized Overstock for search tactics. JCPenny was hit with a penalty in February for similar bad behavior.
2010 Updates
1- Negative Reviews — December: Google decided that being bad to your customers will be bad for your business. Google thus made a rare move and reactively adjusted the algorithm to target sites with negative reviews.
2- Social Signals — December: Google and Bing confirmed the use of social signals in determining ranking, including data from Twitter and Facebook. This was a relatively new development for Google, says Matt Cutts.
3- Instant Previews – November: Google launched a magnifying glass icon on Google search results, which allowed users to quickly view a preview of landing pages directly from SERPs. This focused on improving landing page quality, design and usability.
4- Google Instant – September: Google launched its Google Instant, displaying search results as a query was being typed. It made fewer changes to SEO than the average algorithm update and it had a fairly small impact.
5- Brand Update — August: Google began to allow the same domain to appear multiple times on a SERP. This was not a traditional algorithm update but it increased the chances of one domain dominating the Google search results.
6- Caffeine (Rollout) — June: It took months of testing before Google finally finished rolling out the Caffeine infrastructure, which not only boosted Google’s raw speed, but also integrated crawling and indexation much more tightly. It resulted in a 50% fresher index.
7- May Day — May: In late April and early May, webmasters noticed significant drops in their long-tail traffic. A while later it was confirmed by Matt Cutts that it was the impact of an algorithm change, May Day. The sites with large-scale thin content were hit hard with this update.
8- Google Places — April: Although the Places pages were rolled out in September 2009, these were actually a part of Google Maps. Google’s Local Business Center was re-branded as Google Places, integrated the Places pages more closely with local search results and adding features like new local advertising options.
2009 Updates
1- Real-time Search — December: Google launches real time search results for real – Twitter feeds, Google News, newly indexed content and a number of other sources were integrated into a real-time feed on some SERPs.
2- Caffeine (Preview) — August: Google released a preview of a massive infrastructure change, which was designed to speed crawling, expand the index and integrate indexation and ranking in nearly real-time. The timeline spanned across months with the final rollout starting in the US in early 2010 and lasting until summer.
3- Vince — February: SEOs reported a major update seemingly in the favour of big brands with very profound, long-term implications. However, Google’s Matt Cutts called it a minor change.
4- Rel-canonical Tag — February: Google, Microsoft and Yahoo jointly announced support for the Canonical Tag, which was the most important advancement in SEO practices since sitemaps. It allowed webmasters to send canonicalization signals to search bots without impacting human visitors.
2008 Updates
1- Google Suggest — August: Google introduced Google Suggest feature, displaying suggested searches in a dropdown below the search box while visitors typed their queries.
2- Dewey — April: A large-scale shuffle was reported at the end of March and into early April. Nothing was clear but some suspected that Google was pushing its own internal properties including Google Books.
2007 Updates
1- Buffy — June: The Buffy update was christened in the honour of Vanessa Fox who was leaving Google. Matt Cutts said that Buffy was just an accumulation of smaller changes.
2- Universal Search – May: Google integrated traditional search results with News, Video, Images, Local and other verticals. The old 10-listing SERP was officially dead.
2006 Updates
1- False Alarm — December: Google reported no major changes but there were stirrings about an update in December and some reports of major ranking changes in November.
2- Supplemental update – November: Google seemed to make changes to the supplemental index and the treatment of filtered pages, throughout 2006. Google claimed in late 2006 that the supplemental update was not a penalty (even if it sometimes felt that way).
2005 Updates
1- Big Daddy — December: Big Daddy was an infrastructure update, just like Caffeine and it rolled out over a few months. This update finally wrapped up in March 2006 and changed the way Google handled URL canonicalization.
2- Google Local/Maps – October: After launching the Local Business Center in March 2005 and encouraging businesses to update their information, Google merged its Maps data into the Local Business Center.
3- Jagger — October: Google released a series of updates, mostly targeting low-quality links like reciprocal links, link farms and paid links. Jagger rolled out in at least 3 stages, from roughly September 2005 to November 2005, with the greatest impact occurring in October.
4- Gilligan — September: This update is also called the False update. Webmasters saw changes but Google claimed that no major algorithm update occurred. Google’s Matt Cutts says this was not an update.
5- XML Sitemaps — June: Google allowed webmasters to submit XML sitemaps via Webmaster Tools, bypassing traditional HTML sitemaps and giving SEOs direct (albeit minor) influence over crawling and indexation.
6- Personalized Search — June: Google re-launched personal search, this time it was really personal unlike Google’s previous attempts at personalization. This 2005 roll-out of personalized search tapped directly into users using their search histories to automatically adjust results. Although the impact of this update was small at first but Google claimed to further use search history for many applications.
7- Bourbon — May: Google’s Matt Cutts announced that Google was rolling out something like 3.5 changes in search quality. Webmaster World members speculated that Bourbon changed how duplicate content and non-canonical (www vs. non-www) URLs were treated.
8- Allegra — February: Webmasters witnessed ranking changes although the details of this update were unclear. Some thought that Allegra affected the sandbox while others believed that LSI had been tweaked. Some also speculated that Google was penalizing suspicious links.
9- Nofollow — January: Google, Yahoo and Microsoft collectively unite on support for nofollow attribute for links and introduced NoFollow to combat spam and control outbound link quality. This Nofollow helped in cleaning up spammy links such as the spammy blog comments. It was not a traditional algorithm update but this change had a significant impact on the link graph over a gradual period of time.
2004 Updates
1- Google IPO — August: This was not an algorithm update but it is still marked as a major event in Google’s history. Google sold 19M shares, raised $1.67B in capital and set their market value at over $20B. By January 2005, Google share prices more than doubled.
2- Brandy — February: Google rolled out a variety of changes including a massive index expansion, Latent Semantic Indexing (LSI), increased attention to anchor text relevance and the concept of link neighbourhoods. LSI basically expanded Google’s ability to understand synonyms, taking keyword analysis to the next level.
3- Austin — January: This update came in to clean up what the Florida update had missed. Google continued to crack-down on deceptive on-page tactics like invisible text and META-tag stuffing. Some speculated that Google put the Hilltop algorithm into play, beginning to take page relevance seriously.
2003 Updates
1- Florida — November: The Florida update put updates and probably the SEO industry on the map. Several sites lost ranking, which turned many business owners furious. This update by Google sounded the death knell for low-value late 90s SEO tactics including things like keyword stuffing. It left many people wondering – what happened to their site on Google.
2- Supplemental Index — September: Google split off some results into the supplemental index so as to order to index more documents without sacrificing performance.
3- Fritz – July: The monthly Google Dance finally came to an end with the Fritz update. Rather than completely revamping the index on a roughly monthly basis, Google chose to switch to an incremental approach with the index changing daily.
4- Esmeralda — June: This update marked the last of the regular monthly Google updates. After this, a more continuous update process started to emerge, replacing the Google Dance with Everflux. Google update Esmerelda probably heralded some major infrastructure changes at Google.
5- Dominic — May: Many changes were observed in May but the exact nature of Dominic was unclear. Google bots Freshbot and Deepcrawler scoured the web with several sites reporting bounces. The way Google counted or reported back links seemed to change dramatically.
6- Cassandra – April: Google cracked down on some basic link-quality issues like massive linking from co-owned domains. This update also hit hard on hidden text and hidden links.
7- Boston – February: This was the first named Google update and was announced at SES Boston. Originally, Google aimed at a major monthly update because of which the first few updates were a combination of algorithm changes and major index refreshes (called Google Dance). Once the updates became more frequent, the idea of monthly update died.
2002 Updates
1- 1st Documented Update — September: Before the first named update named Boston, a major shuffle was observed in the fall of 2002. The details are unclear but this appeared to be something more than the monthly Google Dance and PageRank update.
2000 Updates
1- Google Toolbar — December: Google launched the Google Toolbar along with its own Toolbar PageRank (TBPR).