pnpm is a package manager for NodeJS.

What is a package? Node is a bare-bones runtime framework. Think of it as a car that has an engine, a transmission, 4 wheels and a body. Nothing else. Packages are add-ons that provide additional functions, like a radio or horn.

A package manager is software that allows the downloading, installing and managing of these additons which allow Node to do more.

While there are many package managers, PnPM has an advantage in that it stores all packages in a central repository and shares them across multiple Node projects. This allows for less storage space on the host computer. See pnpm.io for more information.

If you just installed NodeJS, then you can just proceed with installing pnpm. However, if you have had Node for a while, make sure it is updated.

Do the following:
1- go to nodejs.org and check what is the version number to the current LTS (long term support).
2- open a Terminal (Mac) or Command Prompt (Windows).

3- Type "node -v", press Enter.
4- If the numbers match, proceed to install or active pnpm. If not, update Node by:

a- Type "npm i -g n", press Enter.
If an error appears:
i-  On Mac, add "sudo" to the front of the command. Press Enter and type your password when requested.
ii- On Windows, close Command Prompt and re-open it as an Administrator. Then type the command again.

With the new "n" package installed, type "n [current LTS version number]", for example "n 18.15". For Mac, add "sudo" to the front of the command, (e.g. sudo n 18.15).

This will update Node to the latest version.

Now, install pnpm in one of two ways:

1- NodeJS comes with a tool called "corepack". We can enable it.

Type "corepack enable", press Enter. This should install pnpm. Then, update it with "corepack prepare pnpm@latest --activate". When done, type "pnpm --version", press Enter. If you see version 6.x or higher, things are good.

2- If corepack does not work, then try installing using npm.
In the terminal type, "npm install -g pnpm", press Enter. When done, type "pnpm --version". If you see version 6.x or higher, things are good.

3- If neither way works, go to https://pnpm.io/installation and look at other options.

With pnpm installed, we are ready and able to install packages to NodeJS in order to build applications.