Text Styles work in exactly the same way. They allow us to keep consistent typography throughout our designs. Something that is often difficult when you have a number of designers working in the same team.
We use them for everything, including Atoms, Molecules, and Organisms.
…I kit Sketch file is made of Symbols. Think of them as folders/groups of text, elements, or layers. Reusable assets that can be easily inserted into design files. And boy, are they time-saving.