uWSGI is a software application that serves as a web server and application server for hosting web applications. It is designed to run Python applications, but it also supports other programming languages. uWSGI communicates with web servers like Nginx or Apache to handle requests and serve content efficiently. One of the key features of uWSGI is its ability to manage multiple application instances, allowing for better performance and scalability. It uses the WSGI (Web Server Gateway Interface) standard, which enables seamless interaction between web servers and Python applications, making it a popular choice for developers.