Conversion Rate Optimization (CRO) refers to the process of improving a website or landing page to increase the percentage of visitors who complete a desired action. This action could be making a purchase, signing up for a newsletter, or filling out a contact form. CRO involves analyzing user behavior, testing various design elements and content, and implementing changes to enhance the overall effectiveness of a webpage in converting visitors into customers or leads. The goal is to maximize the value of the existing traffic without necessarily increasing the number of visitors.