To avoid undesirable content in the search indexes, webmasters can instruct spiders not to crawl certain files or directories through the standard robots.txt file in the root directory of the domain. Additionally, a page can be explicitly excluded from a search engine's database by using a meta tag specific to robots (usually ). When a search engine visits a site, the robots.txt located in the root directory is the first file crawled. The robots.txt file is then parsed and will instruct the robot as to which pages are not to be crawled. As a search engine crawler may keep a cached copy of this file, it may on occasion crawl pages a webmaster does not wish crawled. Pages typically prevented from being crawled include login specific pages such as shopping carts and user-specific content such as search results from internal searches. In March 2007, Google warned webmasters that they should prevent indexing of internal search results because those pages are considered search spam.
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.
Moz Keyword Explorer - Input a keyword in Keyword Explorer and get information like monthly search volume and SERP features (like local packs or featured snippets) that are ranking for that term. The tool extracts accurate search volume data by using live clickstream data. To learn more about how we're producing our keyword data, check out Announcing Keyword Explorer.
So what are the rules of thumb here? First and foremost, it’s very important that your content is easy to read. Of course, you should use your keywords in your text, but don’t stuff your keywords in almost every sentence. In general, if 1 or 2% of all words of your copy, is your keyword, then you’re not overdoing it. Make sure your keywords are well-distributed throughout your text. Don’t put all your keywords in the first paragraph thinking you’re done with that part of the optimization. Naturally spread the keywords throughout your page or post. Use your keywords in a subheading or a couple of subheadings, depending on the length of your page or post. And use the keyword in your page title, first paragraph and your meta description. You can find all of these recommendations in the SEO analysis of Yoast SEO.
Links to your site are extremely valuable – When another website links to yours, search engines consider that an indicator that your site contains valuable content. Not so long ago, getting dozens of links from low-quality sites was all it took to boost your ranking. Today, the value of a link to your site depends on the quality of the site that linked to you. Just a few links to your business from high-traffic sites will do wonders for your ranking!
QUOTE: “To summarize, a lack of helpful SC may be a reason for a Low quality rating, depending on the purpose of the page and the type of website. We have different standards for small websites which exist to serve their communities versus large websites with a large volume of webpages and content. For some types of “webpages,” such as PDFs and JPEG files, we expect no SC at all.” Google Search Quality Evaluator Guidelines 2017
While you can often start with a keyword and create a piece of content around that term, sometimes your content already exists, and you need to figure out how to match it to keywords. To do this, create what's known as a "content to keyword map." Creating this map can help you understand the impact of your existing content and identify weak links or gaps that need filling.