Meta descriptions appear in three main places. First and most importantly, they show up in Google, Bing, and other search engine results as the preview text under your clickable title and green URL. This is the 155–160 character block that explains what your page is about before someone clicks. Second, they populate the description when your URL is shared on Facebook, Twitter, LinkedIn, and other social platforms, though some platforms let you override this with Open Graph tags. Third, they sometimes appear in browser bookmarks or reading lists, though this varies by browser. Google doesn't always use your meta description. If the search engine thinks your written description doesn't match the user's query, it'll pull relevant text from your page content instead. We see this happen 40–60% of the time depending on query specificity. That's why your meta should directly address your primary keyword and user intent, not just be clever marketing copy. The meta description itself lives in your page's HTML head section and looks like this: <meta name="description" content="Your text here">. Users never see this code, only the rendered output in SERPs or social shares. At Ottawa SEO, we write meta descriptions primarily for click-through rate, not rankings, since Google confirmed in 2009 that meta descriptions don't directly influence ranking position. But a compelling meta that beats competitors' snippets can lift CTR by 2–8 percentage points, which does send positive engagement signals over time. We aim for 150–155 characters to avoid truncation on mobile, front-load the value proposition, and include the primary keyword naturally since Google bolds matching terms in the SERP. One gotcha: if you leave the meta description blank, Google writes one for you by pulling sentences from your content. Sometimes that works fine. Usually it's generic and misses the persuasive angle you'd write manually. For commercial pages and anything competing in SERPs, always write your own.