Node.js is a popular open source, cross-platform JavaScript runtime environment. If you want to run Node.js applications on your computer or server, then you need to install Node.js first. But how to ensure that Node.js has been installed successfully? This article will introduce how to determine whether Node.js is installed under different operating systems.
Determine whether Node.js is installed under Linux system
Under Linux system, you can determine whether Node.js has been installed successfully by checking the version number. Enter the following command in the terminal:
node -v
If Node.js is installed on your system, the terminal will display its version number. If there is no output in the terminal, you need to install Node.js first.
If you are using Ubuntu or Debian system, you can install Node.js through apt-get command.
Enter the following command in the terminal:
sudo apt-get install nodejs
After the installation is completed, you can enter again:
node -v
to confirm whether the installation is successful.
Determine whether to install Node.js under Windows system
Under Windows system, you can enter the following command in the command prompt window (CMD):
where node
If you Node.js is installed in the system, and the command prompt will output the path where Node.js is located. If there is no output in the command prompt, you need to install Node.js.
You can download the Windows version of Node.js from the Node.js official website for installation. The download address is https://nodejs.org/en/download/.
Determine whether to install Node.js under macOS system
Under macOS system, you can enter the following command in the terminal:
node -v
If Node is installed in your system. js, the terminal will display its version number. If there is no output in the terminal, you need to install Node.js.
You can download the macOS version of Node.js from the official website of Node.js for installation. The download address is https://nodejs.org/en/download/.
Summary
Node.js is a very popular JavaScript running environment. If you want to run Node.js applications on your own computer or server, you need to install it first. In different operating systems, you can use different commands to determine whether Node.js has been installed successfully. If it is not installed, you can go to the official website of Node.js to download the version suitable for your operating system and install it.
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