In order to have multiple versions of NodeJS installed. For example, because you have a VPS that runs an outdated version of NodeJS. Then you can easily fix this without modifying the system or messing with the package manager. Using the Node Version Manager (nvm) script, you can easily install and use different versions of NodeJS.

Portable installation:


cd ~
git clone https://github.com/nvm-sh/nvm.git .nvm
cd .nvm
git checkout v0.39.3

Usage:


source ~/.nvm/nvm.sh

# install a specific version, or --lts for the latest LTS version
nvm install --lts

# use a specific version
nvm use --lts
# check to see it really changed
node -v

# switch back to system installed
nvm use system
# check to see it really changed back
node -v

More complete list of useful examples:


Example:
  nvm install 8.0.0                     Install a specific version number
  nvm use 8.0                           Use the latest available 8.0.x release
  nvm run 6.10.3 app.js                 Run app.js using node 6.10.3
  nvm exec 4.8.3 node app.js            Run `node app.js` with the PATH pointing to node 4.8.3
  nvm alias default 8.1.0               Set default node version on a shell
  nvm alias default node                Always default to the latest available node version on a shell

  nvm install node                      Install the latest available version
  nvm use node                          Use the latest version
  nvm install --lts                     Install the latest LTS version
  nvm use --lts                         Use the latest LTS version