DOM Custom events, which are often known as synthetic events, are events that allow you to create and dispatch events, causing communication between several parts of an application. This is often used to cause specific actions to happen when one of these events is triggered.
There are a few steps to this and the first is to define the custom event by using the CustomEvent constructor. After this you can dispatch it by using dispatchEvent() and then listen for the custom event by using addEventListener. If done correctly the whole thing should work together and you should see the custom event be triggered
These are used because they improve the developer and user experience of the website as this makes them more interactive and more professional. Using this can also have other improvements including improving the workflow in teams and making it easier for multiple people to work together to accomplish complex tasks.
Overall, DOM custom events are used to create and dispatch events creating communication between different parts of an application. This can make the website more interactive while also being more efficient and interactive for both the developers and users