Images improve user experience but can slow down your site and are invisible to search engines unless optimized properly. Image SEO involves compressing file sizes for faster loading, using descriptive file names (like “seo-checklist.png” instead of “IMG1234.png”), and adding alt text that describes the image using relevant keywords — this also helps with accessibility and image search rankings. Internal linking means linking from one page on your website to another relevant page. This helps search engines discover and understand your site structure, spreads “link authority” across pages, and keeps visitors engaged longer by guiding them to related content.