Image optimization in WordPress is the process of reducing the file size of images while maintaining quality to improve website performance. Optimized images load faster, enhancing user experience and boosting SEO rankings. Techniques include resizing images, compressing files, and using modern formats like WebP. WordPress offers built-in tools and plugins like Smush, Imagify, or ShortPixel to automate optimization. Additionally, using responsive images ensures they adapt to various screen sizes, improving mobile performance. Proper image optimization reduces server load, increases page speed, and can significantly impact site traffic and engagement, making it essential for an efficient and user-friendly WordPress website.