How Search Engines Work?

World around has turned Digital making everyone now open a digital device and search for something daily, actually many times a day but have you ever thought of knowing how these search engines work and how are results that best answers your search query thrown on your screen. Here is the answer for your question. 

With no search engines there would be no access to the world of information. So let see how these search engines work..

Before proceeding further lets understand what a search engine is? A web search engine is a software system that searches the world wide web for the requested search query and gathers all the information relevant and throws them in an order, sorted based on the respective search engines algorithms.

So, How do they perform this job of finding results? For this question to be answered, lets move to the main point of How do Search Engines work? 

Search Engines usually perform 3 different activities as Crawling, to discover content over the web; Indexing, to track and store the content crawled; and Retrieving, fetch relevant content for the search query of a user in the search engine.

Crawling:

The whole work of a Search Engine starts with Crawling which is the all about acquisition of data about a website. 

As a part of this step, websites are scanned and details of each page like titles, descriptions, images, keywords, other linked pages, etc.is collected. Some other crawlers also collect details about page layout, if the links pointing are crammed in, where the advertisements if any are to be placed etc.

A Search Engine's automated robots also called Spiders visit page after page as quick as possible by following various links available. 

A web crawler visits a page and then collects all the links in the page and adds them to the queue of links to be crawled and then do the same for the next links in queue. Crawlers also visit back old sites to look for any updates of the content. With that said, any site or page linked to an already existing indexed page will be crawled eventually. The rate at which sites are crawled varies from site to site, some are crawled more frequently while some others are crawled to a great depth.

Indexing:
Indexing is the step that falls after crawling. A site or a page when crawled is further processed and stored in a database.
Imagine making a list of all house addresses in your town, their owners details, tenants details, floor count, etc. Crawling is going through each house whereas indexing is listing them in your storage space.
This is wrt a small town, now apply the same task to the whole world. That's a simple easy to understand version of what search engines like Google does, storing all the data collected in their huge and vast data centers in the thousands and thousands of petabyte worth of drives.

Retrieving and Ranking:
Retrieving is the process of returning the most relevant page results for your search query. Each Search Engine has its own search criteria based on which the results are displayed to match your search query at best after going through the billions and trillions of pages in their database.
Search Engines are now keeping their search algorithms in mystery to avoid web creators from unfairly climbing the top as in the early days of Search Engines usage.
If you feel still confused a bit or want to have more understanding of a search engine works, here, go through this video below.

How Are Search Engines So Fast? 

Have you ever come across the problem searching your computer for a file that has been saved in an unnoticed location by mistake and closed. Remember how slow your system works for searching that file from an unknown location from the storage of just a few hundreds of files.Now go to a search engine like google or bing or any other and search for a query, you get the results at the blink of an eye. How do you think is this possible for search engines to work so fast?Because search engines unlike our computers won't look for each and every file every time you do a search. They have the pages crawled and indexed and when searched for a query, it takes very less time to retrieve the stored results on to the screen. 

How do search engines rank websites?
That used to be a very easy job for search engines to rank websites in the beginning. It just is the matter of finding the pages with keywords used in the pages and build back links. Thus making the job of an SEO simple by just filling the page with keywords multiple times and building huge links in whatever and every means possible. But this turned out the search results spamy.
Now Search Engines turned far smarter that they developed Algorithms that use various factors to rank the web pages. Few of the vast list of factors include but nor limited to keywords in the page content, on-page factors, off-page factors, social popularity, content quality, backlinks quality and quantity, etc.
Websites that rank better get positioned in the best places in the search results page.

Why do search engines give different results?
Yes, Google search results are not the same for everyone and vary from person to person and different from computer to computer. This is to better facilitate the user with their interests. Few reasons behind seeing different results are your physical location, search history, etc.

How do search engines make money?
While every search results so accurately and perfectly delivered at free of cost, what do you think will run these search engines to pay for its employees? Its obviously their ad network that serve the purpose.

When you search for a query along with the results, search engines like google also some most relevant ads to the right and on the top of the SERP. Those ads that you see around the search results are one of the money earners.
About 85% of the money that Google makes is from advertising. Even Gmail is a way for advertising that forms a part of the earnings. Records show that for every search made Google earns around $50.

What Search Engines exist?
There are lot of search engines available but as best always stands out, here are a few mostly used search engines Google, Yahoo, Bing, Ask.com, AOL.com, Baidu, Wolframalpha, DuckDuckGo, Archive.org, Yandex.ru

Which is the oldest search engine of the Internet?
Although the web was made public in 1990, until 1993 there is no search engine and all indexes are manually made. The search king Google has arrived in 1998 from then, indexation has started to be taken care by software programs. In the 5 year gap of web search availability and Google's birth around 20 search engines were gloriously enjoying, while many failed later.
webcrawler is the oldest still surviving search engine, Lycos, Altavista, Excite, Yahoo, Dogpile, Ask Jeeves, etc are few familiar ones.

Is Google a search engine or library database?
Google can be counted on as a Search Engine as its free and need no user account to search. Also, Databases have information that is credible and already verified. Whereas Google wont stand that way as a publisher can write any thin of their choice and post in the web.

World around is running on internet for whatever is the purpose, either for transferring information or connecting people across different ends or for any other purpose. Everyone from young to old, poor to rich might have heard the word INTERNET.
So, with internet being so important, have you ever wondered, How this INTERNET WORK? How is information transferred on computers whether they are connected via cables or wireless network? Ok, let me take you on a tour about what is internet and how internet works along with briefing about the key terminology.

How does Internet Work?

The Internet or the world of computers network being a part of everybody life connecting millions and trillions of computers digitally by one means or the other as either cables, fibres or wireless links. Internet is being used by everyone but the purpose might be different like to browse websites, communicate with people wherever they are and at whatever time, download pictures and videos, listen to music or for any other amazing purpose.
So, How does all this information(either textual or pictorial or video or any other format) move in this digital world, internet?
Making a request
So, consider that you opened a website with an image. For the image to load a request will be sent to the respective web server where the image is stored in the form of a Packet.  The packet is directed by special computers named routers and devices called switches from your computer to the web server containing the image you are asking for, wherever the web server might be located either near or in the other world.
The packet moves via the fiber optic cables set under the sea or via satellites.
Receiving Information
Now the packets are opened in the web server and the request raised is understood(like in this case, 'please send the image'), fetched in the web server and the corresponding image is again sent back in the form of packets. As the images are huge they are split into hundreds and thousands of packets to send to the request raiser. These packets not only carry the pieces of the image but also has the information regarding how these images can be reformed to their original shape, where they are going and from where they are coming from(web server details).
Different Routes
Directed by routers and switches, these images are sent to your computer by the web server. The packets may not take the same route, instead routers (as the name itself speaks) will direct the images in the fastest possible route. All the packets may not follow the same order in which they were sent.
Putting the packets back together
Now with all the packets reached your computer, your computer will follow the information sent by the web server, attached to the packets and puts the packets back in order and displays the image.
All this process of raising a request, sending information, receiving information and receiving the packets on your computer and displaying the image, all happens in just far less than a second.

Glossary
Data Packets
Information sent or received is split into small bits of data which is known as packets. Packets carry information about where the data is being sent to, from where the information is being sent, how to reassemble the split data to get the actual information requested. In simple words, a Packet is a virtual parcel that holds all important information like IP address of the computer from where the request is received and the IP address of the web server where the image (in this case considered) is stored.
IP Adress:
IP Address the acronym of Internet Protocol Address, is the unique address of each computer connected to the internet. As houses has postal address, so do computers have this IP address. IP address is a combination of numbers like 198.543.25.11.
Switch:
A smart device that connects different devices to form a network is called Switch. Hubs are other such devices that are simpler comparatively.
Router:
This is another such smart device that directs or routes information around the internet to reach the final destination in the fastest possible way. When packets arrive the router, the IP address is read and then are directed to the destination in the best possible route.
DNS:
A Domain Name System or DNS is a set of  computers standards on how the data is exchanged over the internet. DNS turns user friendly domain names like http://digitalmarketing-guide.blogspot.com into machine understandable IP address.

What are Header Tags and How do they influence Search Rankings

As an SEO, we regularly hear or come across many times header tags. It is of great importance to learn and understand what are header tags and what is their role in placing our website in the best position for the relevant search terms. So, firstly lets see what are header tags.

What are Header Tags?

Header tags as the name itself explains are usually the headings in a post. They are the most emphasized wordings of the text and usually are the largest text to stand out.
For example, in this article the text highlighted above "what are header tags?" is the header tag as it is emphasized and is created as a side heading. To be more clear, Header tags are the phrases that break a post (or the information in a post) depending on the hierarchy of the topic being discussed.

Types of Header Tags

Instead of mentioning as types we can say number of header tags. Header tags usually range from H1 to H6 depending on the depth of heading used. You can have more but in most cases that may not needed. H2 is the secondary sub heading under H1, H3 under H2, .. Usually H1 is considered as the main heading of the most and remaining as sub headings under each other.

As you see in the above header tags hierarchy picture, the hierarchy continues with more sub-header tags under each other.

SEO importance of Header Tags

Having proper and necessary usage of header tags is always a good practice both for the user as well as the search engines. Because, it gives an idea for the reader of the importance of the topic as its emphasized. Also, users or search engines can easily understand what are all the topics being discussed at a glimpse of the headings directly. However, H1 tags do have a little direct impact on the rankings as they are the first emphasized text of the post that hits an importance to the bots, making bots consider and understand what is the post being discussed about and thus displaying the page in search results when some searches for the same topic as mentioned in the header tags.

Using Header tags is still a best practice if properly implemented. Rather than stuffing the header tags with keywords, use them properly with the proper context that the further content will be speaking of.

How to use header tags?

Using of header tags is not a big deal. Simply present the topic being discussed in a better way and you could definitely get benefited.

For example if your target keyword is 'Digital Marketing' then instead of writing a H1 tag as 'Digital Marketing' mention it as "What is Digital Marketing" and explain further about what actually digital marketing is then there are very good chances to win the race(while all other factors are also properly maintained). Relevancy always a point to consider while doing any SEO activity. 

If you plan to stuff header tags with keywords better dont use, as one day or the other your site gets hits by Google Algorithm updates. Instead if you use them perfectly, you definitely can experience the best benefits of using the header tags.

Start using them properly.

How many Header tags can be used?

You can use as many header tags, to be more specific as many H1, H2, H3, .. tags as you need but sure to be using them properly at places needed rather than for ranking purpose or for keyword stuffing.

What tools are used to check Heading tags?

There are various tools that are used to check heading tags through out a website. Few of the good ones include but not limited to SEMRush (specifically the SEMRush Audit Tool), SiteBulb Crawler, DeepCrawl, Screaming Frog or SEO Powersuite Website Auditor.