What is search engine optimization (SEO)?

Search engine optimization is the science of improving a website to increase its visibility on search engine results pages (SERPs) when people search for products or services. SEO aims to get as much organic or unpaid traffic as possible to a website through search engines, such as Google and Bing. The more visibility a website has on search engines, the more likely it is for that brand to capture business.

Website visibility is commonly measured by the placement -- or ranking -- of the site on the SERPs, with companies vying for first-page placement, where they're likely to garner the most attention. Using Google as an example, SERPs often feature ads at the top of the page. Businesses are willing to pay for these positions to ensure placement on that first page. Following these ads are the regular search listings, which marketers and search engines refer to as organic search results. The SEO process aims to increase organic search results for a business, driving organic search traffic to the site. This enables data marketers to distinguish between traffic that comes to a website from other channels, such as paid search, social media, referrals and direct as well as organic search traffic.

Organic search traffic is usually higher quality traffic because people are actively searching for a specific topic, product or service for which a site might rank. If someone finds that site through the search engine, it can lead to better brand engagement.

How does SEO work?

Ranking factors and metrics, such as relevance, authority, keywords, internal and external links, page schema and user experience, play crucial roles as search engines work to deliver the most pertinent results to user queries. Effective SEO requires ongoing analysis and adjustments to stay ahead of changing algorithms and user behaviors.

Search engines work with bots or crawlers to analyze all website pages and download and store that information into a collection known as an index. This index is like a library, and when someone searches for something in it, the search engine acts as the librarian. The search engines render the webpages using Hypertext Markup Language, JavaScript and cascading style sheets to determine how they will appear. Search engine algorithms analyze webpages in the index to determine the order in which those pages should be displayed on the SERP. The search engine pulls and displays relevant information from the search query and shows users content related to their search.

Why is SEO important?

As of September 2024, there are over 4 billion pages indexed on the web, with most online traffic driven by search engines. If search engines don't crawl, index and rank websites, those sites could remain hidden from users. Without SEO, a website's capacity to effectively address searchers' questions or showcase the value of its products or services to potential customers becomes meaningless. SEO increases a website's visibility and drives organic traffic, which can lead to higher conversions and sales. It also builds credibility and trust, as higher-ranking sites are often perceived as being more reputable. Additionally, effective SEO can lead to a better user experience, as it focuses on delivering relevant website content and improving site usability. Therefore, investing in SEO can yield long-term benefits, making it a crucial component of a successful SEO marketing strategy.

What are SERP features?

SERP features are unique elements on Google's SERP that go beyond standard organic listings. They enhance the search experience by providing additional information and functionality for a website, boosting its visibility, traffic and click-through rates. Optimizing for these features increases a website's chances of being prominently displayed in search results.

Commonly used SERP features include the following:

• Rich snippets. These add visual elements or extra details to search results, such as review stars for product ratings or product prices.
• Featured snippets. Featured snippets show a preview of a page's content -- usually a small paragraph -- at the top of the search results.
• People Also Ask. This section on the SERP shows related questions that users might find helpful.
• Video carousels and image packs. These showcase multimedia content relevant to the search.
• Knowledge panels. Knowledge panels display information about entities, including people, places or organizations.

SEO vs. SEM vs. PPC

In digital marketing, strategies such as SEO, search engine marketing (SEM) and pay-per-click (PPC) advertising work together but serve different purposes. To effectively reach their marketing objectives, businesses frequently employ a mix of these strategies.

The following are the key differences and characteristics of each strategy:

• SEO. An SEO strategy focuses on enhancing a website's visibility in search engine results organically. Techniques such as content optimization, building backlinks -- which are links from another website to the business's website -- and improving site structure are commonly used. The goal of SEO is to generate unpaid traffic over the long term, making it a cost-effective strategy.
• SEM. This approach is a combination of both SEO and PPC strategies. It involves promoting a website through paid ads as well as optimizing it for organic search to maximize visibility in search engines.
• PPC. In this paid advertising model, advertisers bid on keywords to display their ads on SERPs. Advertisers pay each time a user clicks on their ad. This provides their website with immediate visibility and traffic, but costs can add up quickly.

What algorithms evaluate for search engine optimization

There are hundreds of factors that go into what content from the index gets displayed in a SERP. However, the following six key factors help determine which results are returned for a search query:

1. Meaning of the query. To return relevant results, the algorithm must first establish what information a person is searching for, referred to as their intent. To understand intent, the algorithm must understand language. Interpreting spelling mistakes, identifying synonyms and recognizing that some words mean different things in different contexts all play into the algorithm understanding searcher intent. For example, search engines must be able to distinguish between "bass" as a fish and "bass" as an instrument. Intent would be based on additional search terms, including historical search and location search to display the correct information.
2. Relevance of webpages. The algorithm analyzes webpage content to assess whether the sites contain information relevant to the person's search. This comes after intent is established. A basic signal for relevance would be if the webpage body copy or page headings include the relevant keywords used in the search. But beyond keyword matching, search engines use aggregated interaction data to determine if the page is relevant to the search query. This looks at anonymized data from previous searches to match the page with the query.
3. Quality of the content. Search engines aim to prioritize the most reliable sources available. The intelligence built into the algorithms can identify which pages demonstrate expertise, authoritativeness and trustworthiness in relation to the intent.
4. Usability of webpages. Web design and accessibility play a big part in improving search engine rankings. The algorithm looks at how the site appears in different browsers, if it's designed for different device types -- such as desktops, tablets and phones -- and if the page loading times work well for searchers with slower internet connections.
5. Context and settings. Search engines and their algorithms use information from past search history and search settings to help determine which results are most useful to a user at that moment. Country and location can be used to deliver content relevant to the area from which someone is searching. For example, someone searching for "football" in New England would get different results than someone entering the same query in England.
6. Security. Websites using HTTPS are favored by algorithms, as they provide users with a secure browsing experience.

SEO benefits

Search engine optimization is an essential marketing activity to make a website or business visible on the web. It also provides companies with the following additional benefits:

• Builds trust and credibility. Sites that rank high on SERPs are considered to be of the highest quality and most trustworthy. Results shown on the first page are the most relevant, providing more credibility for the business or website. Having the right content on the site and a good user experience helps the website rank higher.
• Provides a competitive advantage. Many businesses feel they can't afford to not be on the first page of a search result. But organizations that deploy good SEO consistently can outrank their competition.
• Reaches more people. SEO helps attract any user with intent at any time, regardless of the phase of the customer journey that the user is in. It relies on keywords and phrases to attract target audiences to specific products and services. Businesses can create a list of keywords for which they would like to rank and then build content around those keywords.
• Supports content marketing. Building content around those keywords can help an organization's target audience find the information they seek on their website. Content and SEO work in harmony with each other. A site will rank better by creating useful, high-quality content that's optimized for those keywords. Ensuring the keywords are present in headings, meta descriptions and the body of the content can help improve rankings for those terms.
• Ranks better in local searches. The use of local searches is becoming more common, with users looking for products or services "near me." To improve listings in these searches, a company can create a Google Business Profile and optimize the listing for local searches. Along with that and the localized content on the website, a user will be more likely to see local search results in their queries.
• Enables better understanding of the web environment. By staying current with SEO updates and trends, businesses can better understand how search works and make more informed decisions on how to change and adapt their strategies.
• Relatively inexpensive. Compared to other marketing programs, an SEO strategy is affordable for most organizations, as it can be managed in-house or with the help of outside experts.
• Delivers quantifiable results. Organizations can use tools and analytics data to measure the effectiveness of their SEO efforts. Google Analytics can provide comprehensive data about organic traffic, including which pages customers engaged with and keywords used in a search. That data can be cross-referenced with intended actions taken to see how SEO played a role in customer engagement or acquisition.

SEO techniques

While there's a way to maximize results, fully manipulating search engine algorithms is impossible. Businesses often look to the shortest path toward ideal results with the least amount of effort, but SEO is a long-term project, with daily action and constant activity.

The following are the three main components -- or pillars -- of SEO that go into building effective SEO strategies:

1. Technical SEO. This is the process of completing activities when building or maintaining a website to improve SEO. It often has nothing to do with the content that's on the page itself. Some ways to manipulate technical optimization include having an Extensible Markup Language sitemap, structuring content in a way that's intuitive to user experience and improving site performance -- such as page load times, correct image sizing and the hosting environment. Technical SEO also involves key elements such as Core Web Vitals, mobile-friendliness, usability, HTTPS and avoiding intrusive pop-ups and ads.
2. On-page optimization. This process ensures the content on a website is relevant to the users. This content includes the right keywords or phrases in the headings and body of the copy. It ensures that each page includes meta descriptions, internal links within the site and external links to other reputable sites and a URL with the focus keyword. Website administrators use content management systems (CMSes) to maintain on-page SEO and content.
3. Off-page optimization. This technique is used to enhance a site's rankings through activities outside of the website. This type of activity is driven largely by backlinks. Businesses can generate these from partnerships, social media marketing and guest blogging on other sites.

These three components can help marketers focus on the activities and techniques they can implement to build strong rankings for their websites.

The following are additional techniques marketers can use to help build strong rankings:

• Keyword research and selection. Perform keyword research on the most desirable terms to rank for. Businesses should focus on keywords that receive high search volume to be relevant for search engines. Looking at competitors' top-performing keywords also offers an opportunity to build a strategy to compete with them.
• Create quality content. When the keyword strategy is in place, the content strategy follows. Pages are more likely to appear higher on SERPs when they are created with quality content that's relevant to users and their search queries.
• Develop unique page titles and meta descriptions. Page titles should include the page's focus keyword, and meta descriptions should be brief summaries of what a user should expect to learn on the page. These elements are displayed in SERPs.
• Use PPC to supplement organic traffic. Paid advertising can help improve organic click-through rates by giving marketers an outlet to test title tags and meta descriptions that are shown in SERPs. Ensuring a first-page placement, these ads mimic organic search results to see what copy entices users to click. Marketers can use this information to adjust page titles and meta descriptions with organic results.
• Use alt text with images. Alt text is used to describe an image on a webpage. This is critical for bots crawling the site to understand what the image represents. It also provides a description of the image for visually impaired readers using assistive technology. This also provides marketers with another opportunity to use keywords.
• URL slug. A URL slug is the portion of the URL that's unique to a specific page. This is another area where it's important to put the focus keyword, as it relates to what's on the page.
• Link building. Acquiring backlinks from reputable sites can significantly enhance a site's authority and improve its ranking.

SEO tools

There are hundreds of tools to improve, manage and report on the effectiveness of SEO. Some are free, while others are paid offerings. But they all help marketers research keywords, develop strategies and measure the results of ranking higher on SERPs.

According to MarketWatch and Gartner Peer Insights, the following is a sampling of the different SEO tools available:

• Ahrefs. This tool audits websites and provides keyword, link and ranking profiles. It can also identify which pages perform the best and which ones need improvement.
• Clearscope. Designed for content optimization, this tool offers highly detailed content insights, including page performance, readability and a list of keywords to add to the content. Performance analytics tools show website traffic and link performance.
• Google Analytics and Google Search Console. This platform provides real-time data on the effectiveness of SEO. Combined with Google's Search Console, marketers can monitor website traffic, optimize rankings and make informed decisions about the appearance of a site's search results.
• Google Trends. This free tool looks for content trends for a particular topic, place or time frame. It finds popular topics and long-tail keywords related to them and compares those trends over time.
• HubSpot Website Grader. This free tool delivers report cards with actionable insights about SEO performance. It shows if a website is optimized for mobile, measures website performance and provides security recommendations.
• KWFinder. This keyword research tool is designed to help marketers and website owners identify relevant SEO keywords for their online content.
• Moz. Moz Pro provides search engine optimization through a user-friendly interface and features such as keyword research, link analysis, site audits and rank tracking.
• SE Ranking. This SEO toolkit is tailored for both agencies and in-house professionals. It offers a range of premium options, from in-depth keyword research to reporting features.
• Semrush. This platform is used for keyword research and online ranking data. It gives marketers insights into developing and maintaining keyword strategies. It can also be used to measure SEO performance over time.
• SpyFu. This is a competitor keyword research tool to Google Ads. In addition to the keyword research and data it can produce, it gives detailed insight into competitor SEO and PPC data.
• Yoast SEO. For websites using WordPress as their CMS, Yoast SEO is a plugin used to improve on-page optimization. Users can define the URL slug, meta description and page title. They can also see how the content on their page performs in searches. A checklist of items is available so users can ensure their page is as optimized as possible.

SEO tools are designed to empower marketing teams to develop content that effectively engages their audiences. Explore these free SEO keyword research tools.