Ecommerce SEO is search engine optimization specifically tailored for online stores selling products or services. The goal is ranking product pages, category pages, and supporting content where buyers are actively searching, then converting that traffic into revenue. Unlike content sites chasing informational queries, ecommerce SEO targets commercial and transactional keywords like "buy running shoes Canada" or "best espresso machine under $500." The core difference is scale and structure. A typical ecommerce site has hundreds or thousands of product pages, multiple category levels, filtering systems, and inventory that changes. You need clean URL structures, proper canonicalization when products appear in multiple categories, schema markup for prices and availability, and fast page speed because even a one-second delay cuts conversions. Category pages become your main ranking assets for competitive head terms, while individual product pages target long-tail searches with specific models or attributes. Technical foundations matter more in ecommerce than almost any other site type. Crawl budget becomes real when you have 5,000 SKUs. Faceted navigation creates duplicate content nightmares if you let search engines index every filter combination. Out-of-stock products need strategic handling, not automatic 404s that waste authority. Site speed directly impacts revenue because shoppers bail fast. At Ottawa SEO, we treat ecommerce projects differently from lead-gen or content sites. The priorities shift to product feed optimization, structured data for rich snippets showing price and ratings, internal linking that funnels authority to best-sellers and high-margin items, and content that answers buyer questions without burying the buy button. We also watch for pagination issues, image optimization at scale, and mobile performance since most product browsing happens on phones now. The measurement side changes too. Rankings matter, but conversion rate, average order value, and revenue per session matter more. A third-page ranking that converts at 4% beats a featured snippet that converts at 0.8%. Ecommerce SEO is ultimately about profitable traffic, not just traffic volume.