This panel is used to select pre-defined settings for optimizing your site. Using a preset saves you time so you can focus on other tasks. In case you want to fine-tune your website optimization, you can also test different optimization modes.
Standard - This is a pre-defined configuration without much regard for a high PageSpeed score. Enough to get you up and running.
Medium - This mode is well-balanced and suitable for most cases.
Strong - Includes advanced features like automatic image lazy loading, resource loader, and font definition modification.
Ludicrous - A preset aiming to achieve the highest possible score. It may be suboptimal for very few JavaScript-heavy websites.
Custom - Appears when you make a change in a setting which is part of the pre-defined modes. When you are on Custom, you can fine-tune all your settings based on your performance preferences.
For additional information on which mode to use, please read this article.