 To use npm install, let's go into a clean directory. To prove that I have no tricks up my sleeve, I will show you that there's nothing in that directory using ls. Now I can use npm install and I'll use it to install this one called calse. Now the output from that command generated a lot of warnings, but they're not errors. They're just telling me that we don't have a package JSON file. Don't worry about that now, we will cover it in a few lessons. Do know that this was successful. We were able to add a package calse with version 1.2.1. We have this kind of funny message that says we added nine packages and it did that in 1.35 seconds. These additional packages are dependencies of calse. Don't worry too much about that right now, but if you're curious why there's a discrepancy between this number nine and the one package that we installed, that's it. It's just loading other packages that calse needs to do its work. So what changed? Let's run ls again and see what is in our directory now. We have a node modules directory as well as a package lock file. Let's take a look in node modules and see what is inside there. So these are our nine packages that were installed. Calse is the one that we installed directly but it uses all of these additional programs to do the work that it is doing. So what is that work? Well, let's find out. Now that we have it installed, we can run whatever's inside of it. So we'll open up node modules, see what's inside of there, calse, see what's inside of there. And we have this cli.js. I'm gonna assume that that is our program. So let's run that. Cool. Here we have instructions for the calse program. And while there are a lot of options, using it is pretty simple. We just run the command again and give it some text to shout out. Pretty silly. Now this npm install command is going to work inside whichever directory that we're in, installing those dependencies locally into that folder. I'll prove that by navigating out, making a new directory called non-essential npm, navigating to it and again installing calse. You'll notice that this time I use the iAlias and everything worked the same way. We got the same errors for the package JSON. Notice that the package was installed as well as it's eight other package dependencies. If we run ls in this directory, we see that all of that is installed there. And we can check real quick to verify that the essential npm directory still has all of its node modules and package lock file, which it does.