Node-RED comes with a core set of useful nodes, but there are a growing number of additional nodes available for install from both the Node-RED project as well as the wider community.
You can search for available nodes in the Node-RED library.
From version 0.15 you can install nodes directly using the editor. To do this select
Manage Palette from the menu (top right), and then select the
install tab in the palette.
You can now search for new nodes to install, update, and enable and disable existing nodes.
To install an npm-packaged node, you can either install it locally within your
user data directory (by default,
cd $HOME/.node-red npm install <npm-package-name>
You will then need to stop and restart Node-RED for it to pick-up the new nodes.
During development it is also possible to install nodes by copying their
files into a
nodes directory within your user data directory. If these nodes have any npm
dependencies, they must be also be installed within the user data directory.
This is only really recommended for development purposes.