When I read online articles, they sometimes mention people, places, and things I may not know very much about. Does that happen to you?
If I’m really curious, I will either do a Google search or go to Wikipedia to learn more. BUT it means going off the site I was on, opening a lot of tabs and losing track of where I started my search and why. At least, that is what happens for me.
Apture allows me to stay on the page and instead opens a box with a list of sources for more information about the “word you highlight