Act as a seasoned SEO content writer with over 5 years of experience in optimizing websites for search engines. Write a detailed, 1500-word article explaining the impact of structured data on SEO. Begin by defining structured data and its importance in the context of search engine optimization. Discuss [specific types of structured data], such as schema markup, and how they enhance [search engine visibility] and [user experience]. Provide examples of how implementing structured data can improve [website rankings] and [click-through rates]. Include best practices for integrating structured data into a website, tools for testing and validating structured data, and case studies showcasing successful SEO strategies that leveraged structured data. Conclude with actionable tips for readers to start optimizing their websites with structured data today.