Parallax is the term used to describe when the background image moves at a different speed than the foreground content when scrolling. This effect adds the illusion of depth to your website page and can give a sense of immersion to a user experience.

In the majority of Joomla51 templates, an option is available to set a background image for each block/row of top-# and bottom-# modules. In older templates these options can be found in the Styling tab of your template style settings. For all recent templates the option is in the General -> Modules/Component Styling tab. By default this background image will automatically have a parallax effect applied to it. The extent of the parallax effect can vary depending on the template.

If you wish to disable the parallax effect on background images, you can do so by adding the following CSS to the Custom CSS field of your template style settings. This will disable parallax effect across all module blocks.

.module_block {
    background-position-y: 50% !important;
}
[id^="jarallax"] > div {
    transform: none !important;
}