A node is a single building block in the editor that performs one job. String enough of them together and you’ve described an entire merge.
Each node does exactly one thing and does it well:
Because each node is focused, a complex merge stays understandable – it’s a chain of small, clear steps rather than one tangled rule.
A node takes something in, does its job, and passes something on. Those connection points are its sockets: inputs where data arrives, outputs where the result leaves. You connect an output of one node to the input of another to make data flow from step to step.
A workflow is just nodes wired together toward a result. You add the nodes you need, connect them in the order the work should happen, and the editor runs that little machine for every record in your data.
Look at how nodes connect: What Is a Socket?