Module 1 Lesson 4: The n8n UI & Node Anatomy

The n8n interface is an infinite "Canvas." To build great workflows, you must first understand the workspace and the structure of a single "Node."

1. The Workspace Layout

The Canvas: The main area where you drag and drop nodes.
The Sidebar: Access your Workflows, Credentials, and Executions history.
The Node Panel: On the right, this is where you choose which app to add.
Execution Log: At the bottom, this shows you every time the workflow ran and exactly what data moved through it.

2. Anatomy of a Node

When you double-click a node, you see three main sections:

Parameters: The settings (e.g., "Which Slack channel should I send to?").
Input Data: A preview of the data coming FROM the previous node.
Output Data: A preview of what this node will send TO the next node.

3. The 4 States of a Node

Inactive: Gray. The node exists but won't run.
Loading: Pulse. The node is currently working.
Success: Green border. The node worked perfectly.
Failed: Red border. There was an error (e.g., wrong API key).

4. Expressions (`{ }`)

The most powerful part of the node UI is the Expression Editor.

If you want to use the "Name" from Node A inside the "Message" of Node B, you use curly braces: Hello { $node["Node A"].json["name"] }!.
This is called "Dynamic Mapping."

Exercise: The Canvas Expedition

Open a blank n8n workflow.
Drag the "Schedule" node onto the canvas.
Open the node and set it to run "Every minute."
Add a "No-Op" node (or "Wait" node) connected to it.
In the "Wait" node, try to write an expression that says: "The current time is { new Date() }".
Why is the "Execution History" (Module 1, Lesson 4) the most important tool for debugging?

Summary

The n8n UI is designed for "Visual Braindumping." By understanding the layout and the anatomy of a node, you can move from "Idea" to "Visual Logic" in minutes.

Next Lesson: Principles of design: Common automation use-cases.