What is an event parameter in Google Tag Manager (GTM)?

What is an event parameter in Google Tag Manager (GTM)?
Events are user interactions on your website. They are used to track data on your website.
Events in GA4 and the naming convention to follow when creating them.
An event parameter is a part of the event model in GA4. It represents additional information about the tracked event. Also known as the metadata of the event, it sets the context for the event tracked.
For instance, a user views your product. For tracking data like product name, price, category, variants, title, and other information, an event parameter is used.
Below is an example of an event parameter in the GA4 event tag in GTM.
Check the name and the value of the event parameter.

What are the best practices to name an event parameter in GTM?
- Name of event parameter should be in lower case.
- For an event parameter name with two or more words, use underscore. For instance, view_search_result, and file_download_excel.
- The event parameter name should not consist only of numbers.
- The name of the event parameter should not exceed 40 characters.
- The value of the event parameter should not exceed 100 characters.
Let’s see some real-world examples of creating an event parameter.
1. Tracking purchases on e-commerce website
Jeff owns an e-commerce website. He wants to track purchase events. So whenever a user purchases any product on his website, details like item name, transaction id, value, tax, shipping, currency, and price should be tracked.
The event name and parameters created by Jeff are:

2. Tracking case study downloads
Christina wants to track the details of case studies downloaded by users from her website. The data to be collected is the name of the case study, the date on which it was downloaded, the number of pages of that case study, and the time taken to download the same.
The event name and parameters created by Christina are:

To keep the data in your GTM account structured and orderly, you need to have a naming convention in place.
Hope this guide helps you name your event parameters in a structured way.