A meta description tag is an HTML snippet that lives in your page's <head> section and tells search engines what your page is about. It looks like this: <meta name="description" content="Your summary here">. Google and other engines typically display this text beneath your page title in search results, giving users a preview before they click. The meta description doesn't directly influence rankings—Google confirmed this years ago. What it does affect is click-through rate. A compelling, accurate description can be the difference between someone choosing your result or your competitor's. We've seen CTR jumps of 15–40% on client pages after rewriting vague or missing meta descriptions. Keep it between 150–160 characters. Google sometimes shows up to 320 characters on desktop for certain queries, but mobile typically truncates around 120, so front-load your most important points. Include your primary keyword naturally, because Google bolds matching terms in the snippet, which draws the eye. Google doesn't always use your meta description. If it thinks another part of your page better matches the search query, it'll pull that text instead. This happens in roughly 30–40% of searches. That's fine—it means Google is trying to be relevant. But it also means your meta description should complement your on-page content, not contradict it. At Ottawa SEO, we treat meta descriptions as micro-ads. Each one should answer: what's on this page, why should someone care, and what action can they take? For a local business page, we might write: "Family-owned HVAC repair in Ottawa since 2008. Same-day emergency service, upfront pricing, 5-year parts warranty. Call now for free estimate." That's specific, benefit-driven, and under 160 characters. Avoid duplicating meta descriptions across pages. Every page should have a unique description that reflects its specific content. Duplicate descriptions confuse users and waste the snippet real estate Google gives you. If you have thousands of pages, prioritize your high-traffic and conversion pages first, then template the rest with dynamic variables like product names or categories.