Basics of Crawling and Indexing
No one can think about better page rank and high position in search engine results pages (SERPs) without proper crawling and indexing of the website. This necessity highlights the importance of technical SEO in the e-commerce sector. The high-quality content will not guarantee the rewards unless your site or product pages do not figure in top search results. Understanding the processes of crawling and indexing is crucial for creating SEO friendly pages.
In order to get in search engine results pages the site or web pages should first be crawled and indexed. Search engines use crawlers to get data or information from the World Wide Web. These crawlers or spiders are nothing but programming scripts written using different search algorithms to get data from all over the internet. This process of gathering information from the sites and sending them to search engines is called crawling. Sometimes people get confused that crawling and indexing are the same but they are totally different processes.
The process of crawling starts with seed URLs and sitemaps submitted by the webmasters. The crawler or software agent parses the page and identifies all the hyperlinks. These newly discovered links are added to the URL list (queue) to visit them later. The document object model version of the web page is used for scanning. The crawling process uses many graph search algorithms to explore the web pages and their content. This way the crawlers travel all over the internet by exploring the links which they encounter. In this journey, they collect the words. They also see the location of words on the page where they are used. So they also look into headings, meta- tags, titles and alt texts (for images). The words found in these important places have high value for site ranking. That is why from the SEO angle the important keywords should be placed in the titles and headings.
The organization, arrangement, and storage of the information for later retrieval are known as indexing. In simple terms, the words along with their web page locations are placed in a very large central repository. This giant search index is arranged according to relevancy, popularity and page rank of the pages. It is this indexed database from which data is retrieved when a user makes a search query. The crawling and indexing are never-ending processes and crawlers are always busy to retrieve relevant information from the web network so that up to date information can be provided to the users.
What is crawl budget and why it is needed? The search engines have their own limitations for crawling. The biggest challenge for them is to provide the best answers to search queries in a faster way. Therefore they can’t crawl every page on the web due to time and other constraints. The crawlers need to prioritize the selection of the links when they encounter new ones. But how they decide which links to be discarded or not? Well, when crawlers look for data for a specific topic then they assume that a particular topic must have some important keywords around which the page content is framed and frequently appear in the content. So they eye on these keywords and along with other page rank factors they decide on the priority links. So we can say that keyword research is crucial for SEO friendly content.
Therefore all the pages of a site may not be crawled. The number of pages crawled per domain is called crawl budget. Crawling all the pages of sites also make them slow by sending HTTP requests and downloading the content of the pages.
The next question which comes in our minds is whether my site or blog is crawled at all or not? Well, every site is crawled by spiders or auto bots but the timing and frequency of crawling depend on many factors. There are few sites which are crawled many times in just one minute but at the same time, there are many sites too which are crawled once in 6 months or year. For example “news” sites which are updated regularly every day may get crawlers 2-3 times in one minute. Therefore keeping site updated is the key to attract spiders. If you are suspicious about your site crawling by Google, you can type “site:mysite.com” in the Google search bar. You will see the list of all the pages which are indexed. You can also check Google crawl report by using the Google console. And also check the robot.txt file to see whether any page has crawling permission or not. This file has a set of instructions for crawling and indexing. If any site which does not add SEO value to your site then you can disallow that file.
How I can fetch a particular URL page for crawling? Google provides a facility for making requests for re-crawling. Suppose you have made some modification to your page but still not crawled and showing old content then you can fetch URL from Google Search Console. Again this is a request for re crawling and decision lie with crawlers.
The most important factors which can influence site crawling frequency are backlinks profile and page rank. But why enough quality backlinks and high page rank will increase the frequency of crawling? As pointed earlier that it is not simply possible to crawl trillions of pages on the web network. This will eat too much network bandwidth, overload web servers and will take too much time for crawling and indexing and retrieving information from the too big search index. These hurdles pose great contemporary challenges for search engines. So spiders or auto bots decide the next link on the basis of its relevance and authority. It is natural that pages with more quality backlinks will have important and relevant content. The other advantage is that crawlers find such important pages in less time (too many links point them so because of this rich connectivity they are found easily). The unimportant links or pages are ignored because they have no or low relevancy to the search query topic. Pages with high rank are also crawled more frequently while those with low ranks will not be crawled frequently.
How internal links affect the crawling rate? The good site architecture not only increases user experience but also play a role to attract crawlers. Making the site more accessible for crawlers can increase the crawl rate. If you want that your important pages should be crawled then they should not be too deep in the site hierarchy. A user should find them within 2-3 clicks. The crawlers may ignore too deep pages. The categorization and hierarchical order of product pages should be logical for an e-commerce site.
What should be done for better crawling and indexing? There are many factors which affect the crawling rate and indexing. For example, the historical data can also influence crawling. The search engines believe that older sites can have more credibility and authority. Below are some important suggestions for improving the crawling rate and budget.
Search engines always look for fresh and unique content so updating pages with new texts, videos, images etc.can help in frequent crawling.
The more external links from credible and authentic sites give positive signals for the quality content on your site. Earning backlinks with white hat practices in an ethical manner will improve both crawling and ranking.
Incorporating a good and trusted site’s links of other sites in your content will increase the relevancy of the content. Include links according to the need in a contextual manner.
Submitting proper sitemap helps search engines in crawling.
You should have a good design strategy for your site from the beginning. The smooth and hassle-free navigation will help crawlers. The sites with good architecture can incorporate unlimited pages and avoid major usability issues when they become bulky in a later stage.
Since the crawlers look for unique and value-rich content so they can ignore pages which are having copied or duplicate content.
The crawlers or spiders are nothing but code written to scan and parse the documents. They can’t parse dynamic content like java scripts, flash files, images, video, audio etc. Minimize the dynamic content and use some text or tags which can make understand spiders about the content.
Avoid any kind of black hat link building tactics. These can invite penalty from search engines.
Check disallow and no-index tags to avoid any technical crawling errors. In addition, the low performing pages can be blocked from getting crawled and indexed. So wisely use these tags to improve crawl budget for top and quality pages.
Optimize your anchor texts. These should be unique and contextual. The keywords heavy anchor texts can give signals of spammy behavior. Similar anchor texts can also give an impression of duplicate content.
The frequent shutdowns of web servers decrease the credibility of the site in the eyes of crawlers. The crawlers can reduce the crawling rate for the sites which have bad loading time and are having slow speed. The low speed can take more time for a spider to fetch information from the web servers so they can decrease crawl budget. Once response time reduced the crawling may automatically be increased.