QUOTE: “Another problem we were having was an issue with quality and this was particularly bad (we think of it as around 2008 2009 to 2011) we were getting lots of complaints about low-quality content and they were right. We were seeing the same low-quality thing but our relevance metrics kept going up and that’s because the low-quality pages can be very relevant. This is basically the definition of a content farm in our in our vision of the world so we thought we were doing great our numbers were saying we were doing great and we were delivering a terrible user experience and turned out we weren’t measuring what we needed to so what we ended up doing was defining an explicit quality metric which got directly at the issue of quality it’s not the same as relevance …. and it enabled us to develop quality related signals separate from relevant signals and really improve them independently so when the metrics missed something what ranking engineers need to do is fix the rating guidelines… or develop new metrics.” SMX West 2016 – How Google Works: A Google Ranking Engineer’s Story (VIDEO)
QUOTE: “I’ve got a slide here where I show I think 8 different URLs you know every single one of these URLs could return completely different content in practice we as humans whenever we look at ‘www.example.com’ or just regular ‘example.com’ or example.com/index or example.com/home.asp we think of it as the same page and in practice it usually is the same page so technically it doesn’t have to be but almost always web servers will return the same content for like these 8 different versions of the URL so that can cause a lot of problems in search engines if rather than having your backlinks all go to one page instead it’s split between (the versions) and it’s a really big headache….how do people fix this well …. the canonical link element” Matt Cutts, Google
By 2004, search engines had incorporated a wide range of undisclosed factors in their ranking algorithms to reduce the impact of link manipulation. In June 2007, The New York Times' Saul Hansell stated Google ranks sites using more than 200 different signals.[26] The leading search engines, Google, Bing, and Yahoo, do not disclose the algorithms they use to rank pages. Some SEO practitioners have studied different approaches to search engine optimization, and have shared their personal opinions.[27] Patents related to search engines can provide information to better understand search engines.[28] In 2005, Google began personalizing search results for each user. Depending on their history of previous searches, Google crafted results for logged in users.[29]
If you don't know the difference between head terms and long-tail keywords, let me explain. Head terms are keywords phrases that are generally shorter and more generic -- they're typically just one to three words in length, depending on who you talk to. Long-tail keywords, on the other hand, are longer keyword phrases usually containing three or more words.
Redirecting is the act of sending a user to a different URL than the one initially requested. There are many good reasons to redirect from one URL to another, for example, when a website moves to a new address. However, some redirects are designed to deceive search engines and users. These are a very poor user experience, and users may feel tricked or confused. We will call these “sneaky redirects.” Sneaky redirects are deceptive and should be rated Lowest.
Either porn SC or Ads containing porn on non­Porn pages can be very distracting or even upsetting to users. Please refresh the page a few times to see the range of Ads that appear, and use your knowledge of the locale and cultural sensitivities to make your rating. For example, an ad for a model in a revealing bikini is probably acceptable on a site that sells bathing suits. However, an extremely graphic porn ad may warrant a Low (or even Lowest) rating.”
You pay each time a user clicks on an SEM result. You pay nothing when a user clicks on an SEO result. SEM results are paid placements, and your brand is charged each time a user clicks on the result. Therefore, you must have a budget for continually showing SEM ads and using this form of PPC lead generation. On the flip side, you are never charged when a user clicks on an organic search result.

Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses hidden text, either as text colored similar to the background, in an invisible div, or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking. Another category sometimes used is grey hat SEO. This is in between black hat and white hat approaches, where the methods employed avoid the site being penalized but do not act in producing the best content for users. Grey hat SEO is entirely focused on improving search engine rankings.
QUOTE: “Cleaning up these kinds of link issue can take considerable time to be reflected by our algorithms (we don’t have a specific time in mind, but the mentioned 6-12 months is probably on the safe side). In general, you won’t see a jump up in rankings afterwards because our algorithms attempt to ignore the links already, but it makes it easier for us to trust the site later on.” John Mueller, Google, 2018

In Keyword Planner, formerly known as the Keyword Tool, you can get search volume and traffic estimates for keywords you're considering. Unfortunately, when Google transitioned from Keyword Tool to Keyword Planner, they stripped out a lot of the more interesting functionality. But you can make up for it a bit if you take the information you learn from Keyword Planner and use Google Trends to fill in some blanks.

For example, let’s say you were running the website of an online pet store. You might be wise to create one keyword grouping for all your dog-related products, then one for all of your parakeet-related projects, etc. The next step would be to segment each individual group into smaller subgroups (parakeet cages, parakeet toys, parakeet snacks) and then even smaller groups for each type of product (low-fat parakeet snacks, luxury parakeet snacks… you get the idea). Now your pet store can create individual pages optimized for each small keyword group.

Keyword analysis. From nomination, further identify a targeted list of key­words and phrases. Review competitive lists and other pertinent industry sources. Use your preliminary list to determine an indicative number of recent search engine queries and how many websites are competing for each key­word. Prioritize keywords and phrases, plurals, singulars and misspellings. (If search users commonly misspell a keyword, you should identify and use it). Please note that Google will try to correct the term when searching, so use this with care.

Place strategic search phrases on pages. Integrate selected keywords into your website source code and existing content on designated pages. Make sure to apply a sug­gested guideline of one to three keywords/phrases per content page and add more pages to complete the list. Ensure that related words are used as a natural inclu­sion of your keywords. It helps the search engines quickly determine what the page is about. A natural approach to this works best. In the past, 100 to 300 words on a page was recommended. Many tests show that pages with 800 to 2,000 words can outperform shorter ones. In the end, the users, the marketplace, content and links will determine the popularity and ranking numbers.
The above information does not need to feature on every page, more on a clearly accessible page. However – with Google Quality Raters rating web pages on quality based on Expertise, Authority and Trust (see my recent making high-quality websites post) – ANY signal you can send to an algorithm or human reviewer’s eyes that you are a legitimate business is probably a sensible move at this time (if you have nothing to hide, of course).
The leading search engines, such as Google, Bing and Yahoo!, use crawlers to find pages for their algorithmic search results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are found automatically. The Yahoo! Directory and DMOZ, two major directories which closed in 2014 and 2017 respectively, both required manual submission and human editorial review.[40] Google offers Google Search Console, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are found, especially pages that are not discoverable by automatically following links[41] in addition to their URL submission console.[42] Yahoo! formerly operated a paid submission service that guaranteed crawling for a cost per click;[43] however, this practice was discontinued in 2009.