A Force.com Sites developer primarily designs, develops, and deploys public websites and applications using Salesforce's Force.com platform. Their tasks include creating custom pages, integrating Salesforce data and functionality into the website, implementing security settings, and managing domains. They also work on enhancing site performance and user experience. They often have to work with various stakeholders, like web designers, to ensure the site's functionality aligns with business requirements. Their role also involves troubleshooting and resolving site issues. They need to be proficient in Salesforce technologies, including Apex, Visualforce, and often web technologies like HTML, CSS, and JavaScript.