SEO agencies are specialized companies that help businesses improve their online visibility through search engine optimization. They use various techniques to enhance a website's ranking on search engines like Google, making it easier for potential customers to find the business when searching for relevant products or services. These agencies typically offer a range of services, including keyword research, content creation, and link building. By analyzing a website's performance and implementing effective strategies, SEO agencies aim to drive more organic traffic, ultimately leading to increased sales and brand awareness for their clients.