This tutorial demonstrates how to build a web application in Node.js that uses AssemblyAI's Streaming Speech-to-Text API for real-time transcription and DeepL's API for translation into different languages. The app consists of two parts: backend and frontend. The backend is responsible for securely handling the AssemblyAI and DeepL API keys, while the frontend captures audio from the microphone and sends it to the backend for processing. The final transcription is then translated using DeepL's API and displayed on the screen. This application can be useful for non-English speakers visiting English-speaking countries or for any other real-time translation needs.