n8n basics: triggers, expressions, items and webhooks on one page

The words you'll meet

Trigger

The event that starts a workflow: On a schedule, On chat message, On webhook call or Gmail's On message received. Nothing runs until it fires.

Node

One step on the canvas, like Filter or Gmail: Send a message. Open it, set it, close it.

Item

One record, like one sheet row or one email. A node runs once per item.

Execution

One run of the workflow, with the data each step saw. A failed one points at the red node.

Expressions pull in data

• Anything in double curly brackets is filled in from an earlier step. {{ $json.Time }} becomes 8:00 AM for the first job.
• A simple name takes a dot: {{ $json.Tech }}.
• A name with a space takes brackets and quotes: {{ $json["Tech Email"] }}.
• Form data sent to a webhook sits under body: {{ $json.body.name }}.
• A typed address in To sends every job to one person. An expression sends each one to its own.

Items in action

• Google Sheets: Get row(s) in sheet returns six items, one per row.
• A Filter set to is not empty on Tech passes five. The job with no tech is dropped.
• One Gmail step runs five times, one email per job. You never write a loop.

Test, publish and the clock

Workflow timezone

Set it first: ···, Settings, Timezone. It defaults to New York, so 7am can be the wrong 7am.

Test step, Test workflow

Runs it now while you watch, so you don't wait for the schedule to find a mistake.

Publish

Hands the workflow to its trigger so it runs on its own. Older guides say "activate".

Test URL vs Production URL

The test URL only works while you test in the editor. A live form gets the Production URL, after you publish.