Low-Code, No-Code, aPaaS, and RAD are all related to software development, but they differ in their level of technical expertise required to use them. Low-Code platforms require minimal coding knowledge and are targeted at business users, while No-Code platforms require no coding knowledge at all and are aimed at non-technical users. aPaaS (application Platform as a Service) is a cloud-based platform that provides developers with a complete environment to build, deploy, and manage web applications. RAD (Rapid Application Development) is an older approach that focuses on quickly building functional prototypes of software applications.