Node.js achieves concurrency not by doing many things at once, but by never waiting around doing nothing. Concurrency in Node.js = Handling many requests in overlapping time periods — not true parallelism.
Event Loop: At the core of Node.js is the event loop, which allows it to perform non-blocking I/O operations. When Node.js starts, it initializes the event loop, which continuously checks for tasks in the event queue and executes them in a First In, First Out (FIFO) order.
Asynchronous Programming: Node.js uses asynchronous programming to handle multiple operations simultaneously. This means that while one operation is waiting for a response (like a database query), Node.js can continue executing other tasks.
Worker Threads and Child Processes: For CPU-bound tasks, Node.js can use worker threads and child processes. Worker threads allow you to run JavaScript code in parallel threads, while child processes can run separate instances of Node.js, enabling parallel execution.
0-2 years experience
Non-blocking I/O: Node.js uses non-blocking I/O operations, meaning it doesn’t wait for I/O operations to complete before moving on to the next task. This is particularly useful for I/O-bound tasks like network requests or file system operations.
5-8 years experience
8+ years experience
