NPM Commands

1. To list the packages installed:

Global packages
```
npm ls -g --depth 0
```
Local packages
```
npm ls
```
Specific local package
```
npm ls <package_name>
```

2. To visit the link in the 'repository' field of the package.json:

npm repo

3. To initialize a repo:

Basic use:
```
npm init
```
With all defaults:
```
npm init --y
```

4. To add a package from a GitHub repository:

npm install <repo_link>