What is a search engine?
A search engine consists of two main things: a database of information, and algorithms that compute which results to return and rank for a given query.
In the case of web search engines like Google, the database consists of trillions of web pages, and the algorithms look at hundreds of factors to deliver the most relevant results
How do search engines work?
Search engines work by taking a list of known URLs, which then go to the scheduler. The scheduler decides when to crawl each URL. Crawled pages then go to the parser where vital information is extracted and indexed. Parsed links go to the scheduler, which prioritizes their crawling and re-crawling.
When you search for something, search engines return matching pages, and algorithms rank them by relevance.
Here’s a diagram from Google showing this process:
The work of the search engine is divided into three stages, i.e., crawling, indexing, and retrieval.
This is the first step in which a search engine uses web crawlers to find out the webpages on the World Wide Web. A web crawler is a program used by Google to make an index. It is designed for crawling, which is a process in which the crawler browses the web and stores the information about the webpages visited by it in the form of an index.
So, the search engines have the web crawlers or spiders to perform crawling, and the task of crawler is to visit a web page, read it, and follow the links to other web pages of the site. Each time the crawler visits a webpage, it makes a copy of the page and adds its URL to the index. After adding the URL, it regularly visits the sites like every month or two to look for updates or changes.
In this stage, the copies of webpages made by the crawler during crawling are returned to the search engine and stored in a data centre. Using these copies, the crawler creates the index of the search engine. Each of the webpages that you see on search engine listings is crawled and added to the index by the web crawler. Your website should be in the index only then it will appear in the search engine pages.
We can say that the index is like a huge book which contains a copy of each web page found by the crawler. If any webpage changes, the crawler updates the book with new content.
So, the index comprises the URL of different webpages visited by the crawler and contains the information collected by the crawler. This information is used by search engines to provide the relevant answers to users for their queries. If a page is not added to the index, it will not be available to the users. Indexing is a continuous process; crawlers keep visiting websites to find out new data.
This is the final stage in which the search engine provides the most useful and relevant answers in a particular order in response to a search query submitted by the user. Search engines use algorithms to improve the search results so that only genuine information could reach the users, e.g., PageRank is a popular algorithm used by search engines. It shifts through the pages recorded in the index and shows those webpages on the first page of the results that it thinks are the best.
White Hat SEO Techniques
White Hat SEO refers to the SEO techniques which are in accordance with the SEO guidelines set by the search engines. It means it uses approved search engine optimization techniques to improve the ranking of a site on search engine results pages (SERP).
Unlike Black Hat SEO, it mainly focuses on the human audience as opposed to a search engine. People who are looking for long-term investment on their websites rely on white hat SEO techniques. Examples of White Hat SEO include quality content, internal linking, link building, site optimization, social media marketing, Google Ads, etc.
A list of 6 popular white hat SEO techniques are given below:
- Good content
- Proper use of title, keywords and metatags
- Ease of Navigation
- Site Performance
- Quality Inbound Links
- Mobile Friendliness
A unique, well-written content makes your website appear more trustworthy and valuable to search engines and human visitors. It optimizes your website for search engines, which helps you get higher ranking on the search engine listings as search engines offer the most appropriate website to the end-users for their search.
Proper use of title, keywords and metatags
The information contained in the HTML code is known as Metadata. It provides crawler the information about the site for classification and indexing purposes. So, proper title, keyword, and metatag should be incorporated in the metadata.
Ease of navigation
Search engines also consider the ease of navigation while assessing the usefulness of a site, so avoid the irrelevant links and use universally recognizable links. It is not only important for the users but also for the crawlers who index the sites.
Site and page performance is another factor considered by search engines to assess the sites. The unavailable sites or the unavailable pages cannot be indexed by crawlers of search engines; a week or even a day of non-performing site or pages can adversely affect the site traffic. So, make sure your site loads fast and is accessible all the time.
Quality inbound links
The site must have quality inbound links as search engines regularly assess backlinks for their relevance. If a site is found to have irrelevant backlinks, it will be discounted or penalized by the search engine, e.g., a website about fishing in Kenya containing a number of links from Asian websites about technology will be degraded by the search engines.
Mobile-friendliness has become an important SEO factor as Google started emphasizing mobile results since 2016. The reason for this is that there is a tremendous increase in the mobile users browsing content on their mobile phones. So, make sure you have a mobile-friendly site.