WHAT ?
Node.js® is a JavaScript runtime built on Chrome’s V8 JavaScript engine. It’s an open source server environment. Node.js is free. Node.js runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.). Node.js uses JavaScript on the server.
WHY ?
Common tasks for a web server can be to open a file on the server and return the content to the client. Here is how PHP or ASP handles a file request: One, sends the task to the computer’s file system. Two, waits while the file system opens and reads the file. Three, returns the content to the client. And four, being ready to handle the next request. Here is how Node.js handles a file request: One, sends the task to the computer’s file system. Two, be ready to handle the next request. And three, when the file system has opened it read the file and the server returns the content to the client. Node.js eliminates the waiting, and simply continues with the next request. Node.js runs single-threaded, non-blocking, asynchronously programming, which is very memory efficient.
HOW ?
Node.js can generate dynamic page content. It can create, open, read, write, delete, and close files on the server. It can collect form data. And it can add, delete, modify data in your database.
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