nodejs installation and verification

Node.js is a popular JavaScript runtime environment that can be used to develop back-end applications, web applications, and command-line tools. If you are developing these types of applications, installing Node.js can be a worthwhile task. In this article, we will explain how to install Node.js and verify that its installation was successful.

Installing Node.js

Before starting the installation, please make sure that your operating system is updated and the necessary dependencies are installed. You can download the latest version for your operating system from the official Node.js website (https://nodejs.org/en/). The installation steps are as follows:

1. Open the Node.js official website and choose to download the file suitable for your operating system.
2. Open the downloaded installation program and follow the prompts to install. During the installation process, you can choose to install the built-in npm (Node Package Manager) package manager.
3. After the installation is complete, open a terminal and enter the following command to verify whether Node.js has been installed correctly.

node -v

The output result should be the installed Node.js version number, such as "v16.3.0".

Verify Node.js

Once you have installed Node.js following the steps above, you can try running some simple commands to test whether it is working properly. Here are some common Node.js commands and their corresponding output:

1. Command: node
   Output:

   console.log('Hello, World! ');
   Hello, World!

   This command outputs the string "Hello, World!" to the console. You can modify the output as needed.

2. Command: node -e "console.log(1 2)"
   Output:
   3

   This command executes a simple JavaScript Expression, the output result is 3.

3. Command: node -e "console.log(Math.random())"
   Output:
   0.994292396123356

   This command uses JavaScript built-in The Math.random() function generates a random number between 0 and 1.

4. Command: npm -v
   Output:
   7.15.0

   This command verifies that the npm package manager has been installed correctly and outputs The current version number of npm.

Summary

By installing and validating Node.js, you are successfully ready to develop applications, web applications, and command-line tools. In this article, we learned how to download and install Node.js and test its functionality by running some simple commands. Now you can continue learning how to build feature-rich applications using Node.js.

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