The purpose of a tech stack in software development is to define the combination of technologies used to build, deploy, and maintain applications. It includes programming languages, frameworks, libraries, and tools that work together to provide a cohesive environment for developers. A well-defined tech stack can enhance efficiency, facilitate collaboration, and ensure smoother integration of components. Furthermore, choosing the appropriate tech stack impacts a project’s scalability, security, and performance, influencing the overall success and longevity of software applications.