Multi-threaded applications are programs that can perform multiple tasks simultaneously by using multiple threads of execution. A thread is a lightweight process that can run independently, allowing the application to handle various operations at the same time. This can improve performance, especially in tasks that require significant processing power or involve waiting for external resources, like network requests. In a multi-threaded application, threads can share resources and communicate with each other, which helps in efficiently managing tasks. For example, a web server can handle multiple user requests concurrently, ensuring faster response times and better resource utilization. This design is commonly used in modern software development to enhance user experience and system efficiency.