SEM search placements include an “Ad” designation. SEO does not. Search results that appear as a result of SEM or SEO look different on SERPs. Paid ads that receive placement through SEM tactics are often identified as an ad (e.g., by an icon appearing next to the placement), whereas the search results that appear as a result of organic SEO are not marked in such manner.
At first glance, the Ads or SC appear to be MC. Some users may interact with Ads or SC, believing that the Ads or SC is the MC.Ads appear to be SC (links) where the user would expect that clicking the link will take them to another page within the same website, but actually take them to a different website. Some users may feel surprised or confused when clicking SC or links that go to a page on a completely different website.
QUOTE: “News and current events: news about important topics such as international events, business, politics, science, technology, etc. Keep in mind that not all news articles are necessarily considered YMYL (e.g., sports, entertainment, and everyday lifestyle topics are generally not YMYL). Please use your judgment and knowledge of your locale. ● Civics, government, and law: information important to maintaining an informed citizenry, such as information about voting, government agencies, public institutions, social services, and legal issues (e.g., divorce, child custody, adoption, creating a will, etc.). ● Finance: financial advice or information regarding investments, taxes, retirement planning, loans, banking, or insurance, particularly webpages that allow people to make purchases or transfer money online. ● Shopping: information about or services related to research or purchase of goods/services, particularly webpages that allow people to make purchases online. ● Health and safety: advice or information about medical issues, drugs, hospitals, emergency preparedness, how dangerous an activity is, etc. ● Groups of people: information about or claims related to groups of people, including but not limited to those grouped on the basis of race or ethnic origin, religion, disability, age, nationality, veteran status, sexual orientation, gender or gender identity. ● Other: there are many other topics related to big decisions or important aspects of people’s lives which thus may be considered YMYL, such as fitness and nutrition, housing information, choosing a college, finding a job, etc.” Google Search Quality Evaluator Guidelines 2019

Many search engine marketers think who you link out to (and who links to you) helps determine a topical community of sites in any field or a hub of authority. Quite simply, you want to be in that hub, at the centre if possible (however unlikely), but at least in it. I like to think of this one as a good thing to remember in the future as search engines get even better at determining topical relevancy of pages, but I have never actually seen any granular ranking benefit (for the page in question) from linking out.
Another illicit practice is to place "doorway" pages loaded with keywords on the client's site somewhere. The SEO promises this will make the page more relevant for more queries. This is inherently false since individual pages are rarely relevant for a wide range of keywords. More insidious, however, is that these doorway pages often contain hidden links to the SEO's other clients as well. Such doorway pages drain away the link popularity of a site and route it to the SEO and its other clients, which may include sites with unsavory or illegal content.
Alt text (alternative text), also known as "alt attributes" describe the appearance and function of an image on a page. Alt text uses: 1. Adding alternative text to photos is first and foremost a principle of web accessibility. Visually impaired users using screen readers will be read an alt attribute to better understand an on-page image. 2. Alt tags will be displayed in place of an image if an image file cannot be loaded. 3. Alt tags provide better image context/descriptions to search engine crawlers, helping them to index an image properly.
Understand and accept why Google ranks your competition above you – they are either: more relevant and more popular, more relevant and more reputable, better user experience or manipulating backlinks better than you. Understand that everyone at the top of Google falls into those categories and formulate your own strategy to compete – relying on Google to take action on your behalf is VERY probably not going to happen.
QUOTE: “So there’s three things that you really want to do well if you want to be the world’s best search engine you want to crawl the web comprehensively and deeply you want to index those pages and then you want to rank or serve those pages and return the most relevant ones first….. we basically take PageRank as the primary determinant and the more PageRank you have that is the more people who link to you and the more reputable those people are the more likely it is we’re going to discover your page…. we use page rank as well as over 200 other factors in our rankings to try to say okay maybe this document is really authoritative it has a lot of reputation because it has a lot of PageRank … and that’s kind of the secret sauce trying to figure out a way to combine those 200 different ranking signals in order to find the most relevant document.” Matt Cutts, Google
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.
There are some basic keyword usage rules you should follow to get started. Unique keywords should be employed on each page of your site in the areas that bots and humans normally look to reassure them that you have what they're after. This includes both the title tag and the body of your content, which leads to an important point: the pitfalls of clickbait. You may believe you're enticing more clicks by offering tantalizingly vague titles for your content, but by disguising what the page is actually about, you're opting out of some of the power of keywords.
The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.