SEO How-to, Part 2: Understanding Search Engines

Nearly half of shoppers turn to Google before deciding what to buy and where to buy it. Understanding how Google and other search engines work can help you choose which optimization strategies to apply.

This post is the second installment in my “SEO How-to” series. In “Part 1: Why Use It?,” I addressed the importance of search engine optimization to ecommerce.

Your products may be the highest quality or lowest priced. Your business might be superior to competitors in dozens of ways. But if it does not send proper signals to search engines, your site will not rank highly in organic search results, to drive shoppers.

Search engines utilize sophisticated software supported by vast networks of datacenters. Search engines crawl sites to index pages for quick retrieval and then return search results based on relevance to the query and authority.

…if it does not send proper signals to search engines, your site will not rank highly in organic search results, to drive shoppers.

Crawling and Indexing

The web contains trillions of pages. Search engines use crawlers — also known as robots or, simply, bots — to locate and store all the pages they encounter.

When a crawler hits a page, it records the rendered HTML and catalogs the content. As they digest the page, crawlers discover links to other pages, and the process repeats.

However, some web pages are not crawlable.

For instance, if the page for product X has no inbound links and is only accessible by typing its URL into a browser bar, Google and other search engines will likely not find that page. It will remain unknown until another already-indexed page links to it.

Search Results

Much of SEO involves the algorithms that search engines use to rank organic results.

An algorithm is complex software. It’s so complicated that even the people who develop it struggle to comprehend all of it.

As marketers, much of what we know about search engines’ algorithms derives from their patents, the news they release, and search-performance data aggregated over time across the entire web.

Hundreds of factors determine the ranking of each page. Primary factors are the relevance of the content to the search term, searchers’ experiences on the page, and the quality of other sites that link to the page. Those factors indicate, respectively, relevance, technical aspects, and authority.

• Relevance is based on comparing the content on your page to a searcher’s query and interests. Search engines evaluate all of the words on the page and how they relate to each other and to other pages on the site. That’s how search engines know that a page is about, say, a bass guitar, not a fish.

Consumers tend to blame the search engine for delivering them to lousy sites, rather than blaming the site itself. Thus search engines try to return results for sites that are user-friendly with relevant content.

Moreover, search engines use personalization to improve relevancy. For instance, a search engine would likely know, based on previous searches, whether a searcher is interested in fishing or music. Personalization signals also include a searcher’s location, among other public info.

• Technical SEO includes page speed, navigation, accuracy, and usability — especially on a smartphone.

• Authority signals consider the quality, size, and relevance of the sites that link to a page. A link from, say, The New York Times is much more authoritative than from a little-known blog. Links from quality sites that are topically relevant pass more value. A link from a leading music review site to a bass guitar page passes more authority than from a recipe site.

Think of each link as a vote of value. The more sites that link to your page or your site, the more valuable it likely is. This is the founding principal of Google more than 20 years ago. It remains a major factor in organic search rankings.

See “Part 3: Strategy and Planning.”