How do alt tags contribute to SEO?

Alt tags, or alternative text descriptions added to images, contribute significantly to SEO by providing context for images to search engines. When search engines crawl a webpage, they cannot interpret images the way humans can. Alt tags serve as descriptive text that explains what the image is about, allowing search engines to understand the relevance of the image in relation to the content of the page. This contextual information can help improve a site's visibility in image search results and enhance its overall search engine optimization by correlating images with relevant keywords.

Moreover, using alt tags correctly can also improve accessibility for users with visual impairments who rely on screen readers to understand web content. This not only enhances user experience but can also positively impact SEO since search engines prioritize user-friendly practices.

While aspects like page loading speed, image file size, and visual appeal of webpages are all important factors in web design and user experience, they do not directly relate to the function of alt tags in terms of providing searchable context for images. Hence, focusing on how alt tags enhance the searchability and relevance of images leads to improved search engine rankings.