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MediumQ. No. what-does-http-status-code-404-mean
What does HTTP status code 404 mean?
Last Updated:
AServer error
BResource not found
CUnauthorized
DSuccess
Correct Answer: Resource not foundYour Answer: B
HTTP 404 means the requested resource was not found.
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Node.js is a JavaScript runtime environment built on Chrome's V8 engine that allows JavaScript to run on the server side. Key features: non-blocking asynchronous I/O, event-driven architecture, single-threaded with event loop, npm (Node Package Manager) with millions of packages. Node.js is used for building REST APIs, real-time applications, streaming services, and microservices.
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Express.js is the most popular web framework for Node.js that simplifies building RESTful APIs and web applications. It provides: routing (GET, POST, PUT, DELETE), middleware support, template engines, error handling, and static file serving. Express is minimal and unopinionated, making it flexible for building any type of Node.js application. It is the most widely used Node.js framework.
The Node.js Event Loop allows Node.js to perform non-blocking I/O operations despite JavaScript being single-threaded. When async operations (file read, database query, HTTP request) are initiated, they are delegated to the OS or thread pool. When complete, callbacks are placed in the event queue. The event loop processes callbacks when the call stack is empty, enabling handling thousands of concurrent connections.
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