在使用npm install在node.js中启动项目时感到困惑

Question

Hello I am just a noob and still learning. I have already downloaded and tried the chat tutorial of get-started part from socket.io . Now, I am again learning from another source. What's confusing me is that, do I always have to npm install in the beginning of every project after writing the dependencies in the package.json? Or is there any other way? I would be very glad if you could help me understand my confusion. Thank you!

Answer 1

Yes, before running, all dependencies must be installed. So you must run npm install .

When developing, you can use npm install --save <package_name> to install a dependency and automatically add it to package.json .

Answer 2

NPM means Node Package Manager. It is used to manage your dependencies to other node modules dynamically thanks to a configuration file called package.json . This way you can easily define the exact versions you need or a mask in order to always retrieve the stable ones for instance.

The command npm install allows to interpret your configuration file and then download the good versions (and this recursively).