The Custom HTML Particle acts as an easy substitute to the Custom HTML module in Joomla, or the Text widget in WordPress. It's a quick way to create custom HTML content and add it to your page via either the Layout Manager or the Menu Editor.
The Particle's settings are pretty simple. There is a big field you can insert HTML scripting. You can also edit the Block-level settings to refine the Particle's variations, tag attributes, CSS classes, etc.