Today, I learned about smart guides and how to customize them.
Smart Guides are temporary snap‑to guides that appear when you create or manipulate objects or artboards. These appear when the object is position to a certain point of another object, like the right side or the center.
You can customize these smart guides by going to Preferences, then Smart Guides. This allows you to change the color, change options of what it reveals, change construction guides, and change the snapping tolerance or sensitivity. To turn them off, head to View, then choose Smart Guides.