While doing local development, it's beneficial to (sometimes) disable things such as caching in order to be quicker. Drupal 8 takes caching to a whole new level, so many hook implementations, for example, get cached. To circumvent this, we can use some local settings that disable caching, prevent CSS and JavaScript file aggregation, and do similar things.
These settings are found inside the example.settings.local.php file in the /sites folder of the installation. To benefit from these, you will need to make sure that they are included in your main settings.php file (either by copying them inside or including a file such as this).
A word of caution--do keep in mind that by developing with caching disabled at all times, you ...