Quality Score is a measure used by search engines like Google to check how good and relevant your ads are. It affects where your ad appears in search results and how much you pay per click. The score ranges from 1 to 10, with higher scores meaning better performance. Key factors include how often people click on your ad, how well it matches the keywords, and the quality of the landing page users visit after clicking. Improving these areas can boost your Quality Score, helping you get more visibility while spending less on ads.