A node is the smallest programming unit in KNIME. Each node serves a dedicated task, from very simple ones - like changing the name of a data column - to very complex one - like training a random forest.
After being created, a node needs settings to execute the task.This phase is called configuration. After configuration, a node needs to be executed to actually carry out the assigned task.
The following video shows how to create, configure, execute, and reset a node.