The main idea of Node.js: use non-blocking, event-driven I/O to remain lightweight and efficient in the face of data-intensive real-time applications that run across distributed devices.
Node.js is only an environment - meaning that you have to do everything yourself. There is not a default HTTP server, or any server for that matter.
Naturally, we need to install Node before we can write and execute an app. Installation is straight forward, if you use Windows or OS X; the nodejs.org website offers installers for those operating systems. For Linux, use any package manager. Open up your terminal and type:
sudo apt-get update
sudo apt-get install node
sudo aptitude update
sudo aptitude install node
Node.js is in sid repositories; you may need to add them to your sources list:
sudo echo deb http://ftp.us.debian.org/debian/ sid main > /etc/apt/sources.list.d/sid.list
But be aware that installing sid packages on older systems may break your system. Be careful, and remove /etc/apt/sources.list.d/sid.list after you finish installing Node.
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