Webmasters and content providers began optimizing websites for search engines in the mid-1990s, as the first search engines were cataloging the early Web. Initially, all webmasters only needed to submit the address of a page, or URL, to the various engines which would send a "spider" to "crawl" that page, extract links to other pages from it, and return information found on the page to be indexed.[5] The process involves a search engine spider downloading a page and storing it on the search engine's own server. A second program, known as an indexer, extracts information about the page, such as the words it contains, where they are located, and any weight for specific words, as well as all links the page contains. All of this information is then placed into a scheduler for crawling at a later date.
Ideally, you will have unique pages, with unique page titles and unique page meta descriptions . Google does not seem to use the meta description when ranking your page for specific keyword searches if not relevant and unless you are careful if you might end up just giving spammers free original text for their site and not yours once they scrape your descriptions and put the text in main content on their site. I don’t worry about meta keywords these days as Google and Bing say they either ignore them or use them as spam signals.
You’ll likely compile a lot of keywords. How do you know which to tackle first? It could be a good idea to prioritize high-volume keywords that your competitors are not currently ranking for. On the flip side, you could also see which keywords from your list your competitors are already ranking for and prioritize those. The former is great when you want to take advantage of your competitors’ missed opportunities, while the latter is an aggressive strategy that sets you up to compete for keywords your competitors are already performing well for.
QUOTE: “Anytime you do a bigger change on your website if you redirect a lot of URLs or if you go from one domain to another or if you change your site’s structure then all of that does take time for things to settle down so we can follow that pretty quickly we can definitely forward the signals there but that doesn’t mean that’ll happen from one day to next” John Mueller, Google 2016
So: how to proceed? On the one hand, SEO best practices recommend that you include relevant keywords in a number of high-attention areas on your site, everywhere from the titles and body text of your pages to your URLs to your meta tags to your image file names. On the other hand, successfully optimized websites tend to have thousands or even millions of keywords. You can't very well craft a single, unique page for every one of your keywords; at the same time, you can't try to cram everything onto a handful of pages with keyword stuffing and expect to rank for every individual keyword. It just doesn't work that way.
You don’t want to “keyword stuff” and cram your core keyword and every possible variation of it into your alt attribute. In fact, if it doesn’t fit naturally into the description, don’t include your target keyword here at all. Just be sure not to skip the alt attribute, and try to give a thorough, accurate description of the image (imagine you’re describing it to someone who can’t see it – that’s what it’s there for!).
Google recommends that all websites use https:// when possible. The hostname is where your website is hosted, commonly using the same domain name that you'd use for email. Google differentiates between the "www" and "non-www" version (for example, "www.example.com" or just "example.com"). When adding your website to Search Console, we recommend adding both http:// and https:// versions, as well as the "www" and "non-www" versions.
The reality in 2019 is that if Google classifies your duplicate content as THIN content, or MANIPULATIVE BOILER-PLATE or NEAR DUPLICATE ‘SPUN’ content, then you probably DO have a severe problem that violates Google’s website performance recommendations and this ‘violation’ will need ‘cleaned’ up – if – of course – you intend to rank high in Google.
Robots.txt is not an appropriate or effective way of blocking sensitive or confidential material. It only instructs well-behaved crawlers that the pages are not for them, but it does not prevent your server from delivering those pages to a browser that requests them. One reason is that search engines could still reference the URLs you block (showing just the URL, no title or snippet) if there happen to be links to those URLs somewhere on the Internet (like referrer logs). Also, non-compliant or rogue search engines that don't acknowledge the Robots Exclusion Standard could disobey the instructions of your robots.txt. Finally, a curious user could examine the directories or subdirectories in your robots.txt file and guess the URL of the content that you don't want seen.
Writing blog posts is especially effective for providing different opportunities to land on page one of search engines -- for instance, maybe your eyeglass store’s website is on page three of Google for “eyeglasses,” but your “Best Sunglasses of 2018” blog post is on page one, pulling in an impressive amount of traffic (over time, that blog post could also boost your overall website to page one).
KISS does not mean boring web pages. You can create stunning sites with smashing graphics – but you should build these sites using simple techniques – HTML & CSS, for instance. If you are new to web design, avoid things like Flash and JavaScript, especially for elements like scrolling news tickers, etc. These elements work fine for TV – but only cause problems for website visitors.
However, you may encounter pages with a large amount of spammed forum discussions or spammed user comments. We’ll consider a comment or forum discussion to be “spammed” if someone posts unrelated comments which are not intended to help other users, but rather to advertise a product or create a link to a website. Frequently these comments are posted by a “bot” rather than a real person. Spammed comments are easy to recognize. They may include Ads, download, or other links, or sometimes just short strings of text unrelated to the topic, such as “Good,” “Hello,” “I’m new here,” “How are you today,” etc. Webmasters should find and remove this content because it is a bad user experience.

When using the Keyword Explorer, Ahrefs will also produce the "parent topic" of the keyword you looked up, as you can see in the screenshot above, underneath the Keyword Difficulty meter. A keyword's parent topic is a broader keyword with higher search volume than your intended keyword, but likely has the same audience and ranking potential -- giving you more a valuable SEO opportunity when optimizing a particular blog post or webpage.

And so on and so on. The point of this step isn't to come up with your final list of keyword phrases. You just want to end up with a brain dump of phrases you think potential customers might use to search for content related to that particular topic bucket. We'll narrow the lists down later in the process so you don't have something too unwieldy. Once you have your final list, there are several data-driven tools available to you for finding out which keywords you're most likely to rank well for. 
A navigational page is a simple page on your site that displays the structure of your website, and usually consists of a hierarchical listing of the pages on your site. Visitors may visit this page if they are having problems finding pages on your site. While search engines will also visit this page, getting good crawl coverage of the pages on your site, it's mainly aimed at human visitors.

Ever wonder how major search engines such as Google, Bing and Yahoo rank your website within their searches? Or how content such as videos or local listings are shown and ranked based on what the search engine considers most relevant to users? Welcome to the world of Search Engine Optimization (SEO). This course is the first within the SEO Specialization and it is intended to give you a taste of SEO. You will be introduced to the foundational elements of how search engines work, how the SEO landscape has changed and what you can expect in the future. You discuss core SEO strategies and tactics used to drive more organic search results to a specific website or set of websites, as well as tactics to avoid to prevent penalization from search engines. You will also discover how to position yourself for a successful career in SEO should this subject prove interesting to you. We hope this taste of SEO, will entice you to continue through the Specialization.
While the title tag is effectively your search listing’s headline, the meta description (another meta HTML element that can be updated in your site’s code, but isn’t seen on your actual page) is effectively your site’s additional ad copy. Google takes some liberties with what they display in search results, so your meta description may not always show, but if you have a compelling description of your page that would make folks searching likely to click, you can greatly increase traffic. (Remember: showing up in search results is just the first step! You still need to get searchers to come to your site, and then actually take the action you want.)

Experience can educate you when a page is high-quality and yet receives no traffic. If the page is thin, but is not manipulative, is indeed ‘unique’ and delivers on a purpose with little obvious detectable reason to mark it down, then you can say it is a high-quality page – just with very little search demand for it. Ignored content is not the same as ‘toxic’ content.
To prevent users from linking to one version of a URL and others linking to a different version (this could split the reputation of that content between the URLs), focus on using and referring to one URL in the structure and internal linking of your pages. If you do find that people are accessing the same content through multiple URLs, setting up a 301 redirect32 from non-preferred URLs to the dominant URL is a good solution for this. You may also use canonical URL or use the rel="canonical"33 link element if you cannot redirect.
QUOTE: “Supplementary Content contributes to a good user experience on the page, but does not directly help the page achieve its purpose. SC is created by Webmasters and is an important part of the user experience. One common type of SC is navigation links which allow users to visit other parts of the website. Note that in some cases, content behind tabs may be considered part of the SC of the page.” Google Search Quality Evaluator Guidelines 2017
An authority website is a site that is trusted by its users, the industry it operates in, other websites and search engines. Traditionally a link from an authority website is very valuable, as it’s seen as a vote of confidence. The more of these you have, and the higher quality content you produce, the more likely your own site will become an authority too.
The length of a title tag that Google will show will vary (it’s based on pixels, not character counts) but in general 55-60 characters is a good rule of thumb here. If possible you want to work in your core keyword, and if you can do it in a natural and compelling way, add some related modifiers around that term as well. Keep in mind though: the title tag will frequently be what a searcher sees in search results for your page. It’s the “headline” in organic search results, so you also want to take how clickable your title tag is into account.
WebSite Auditor scans pages for code errors, duplicate content and other structure-related issues they may have. Other than that, there is this on-page optimization module, which allows determining the ideal keyword placement and researches page elements that can be optimized. In WebSite Auditor you can also analyze competitor’s pages to compare of to improve own on-page strategy. There are actually more features, I just won’t be listing all of them here. But this is the best solution with regard to on-page optimization I found so far.
Ideally, you will have unique pages, with unique page titles and unique page meta descriptions . Google does not seem to use the meta description when ranking your page for specific keyword searches if not relevant and unless you are careful if you might end up just giving spammers free original text for their site and not yours once they scrape your descriptions and put the text in main content on their site. I don’t worry about meta keywords these days as Google and Bing say they either ignore them or use them as spam signals.

If you link out to irrelevant sites, Google may ignore the page, too – but again, it depends on the site in question. Who you link to, or HOW you link to, REALLY DOES MATTER – I expect Google to use your linking practices as a potential means by which to classify your site. Affiliate sites, for example, don’t do well in Google these days without some good quality backlinks and higher quality pages.

Onsite, consider linking to your other pages by linking to pages within main content text. I usually only do this when it is relevant – often, I’ll link to relevant pages when the keyword is in the title elements of both pages. I don’t go in for auto-generating links at all. Google has penalised sites for using particular auto link plugins, for instance, so I avoid them.
For instance, you might use Facebook’s Lookalike Audiences to get your message in front of an audience similar to your core demographic. Or, you could pay a social media influencer to share images of your products to her already well-established community. Paid social media can attract new customers to your brand or product, but you’ll want to conduct market research and A/B testing before investing too much in one social media channel.
Submit website to directories (limited use). Professional search marketers don’t sub­mit the URL to the major search engines, but it’s possible to do so. A better and faster way is to get links back to your site naturally. Links get your site indexed by the search engines. However, you should submit your URL to directories such as Yahoo! (paid), Business.com (paid) and DMOZ (free). Some may choose to include AdSense (google.com/adsense) scripts on a new site to get their Google Media bot to visit. It will likely get your pages indexed quickly.