A Junior JavaScript Developer is an entry-level programmer who specializes in using JavaScript to build web applications, websites, and front-end interfaces. They work under the guidance of senior developers to implement interactive features, troubleshoot issues, and improve functionality. Their responsibilities may include writing clean code, debugging, collaborating with designers, and learning new technologies. Typically, they are expected to have a basic understanding of JavaScript, HTML, CSS, and frameworks like React or Vue.js. This role is ideal for those starting their career in web development and looking to gain hands-on experience in a professional setting.