Design.
Typography.

Communication plays a vital role in design. Whether you design websites, mobile apps, or wearable UIs, your creations have to clearly communicate their intent and purpose. And since text does a lot of the heavy lifting in communicating purpose, you need a solid understanding of typography.

AboutAuthorDate
Choosing the Right Font: A Guide to Typography and UXUser Testing Blog
Typography can make your design...or it can break it.freeCodeCampApril 11th, 2017
Typography for User InterfacesViljami SalminenJune 21st, 2016
Mobile UX: Great Typography Enables Clear CommunicationUX PlanetMay 23rd, 2016
The UX of typography explainedCreative BloqFebruary 25th, 2016
4 tips on typography in UI designInvision BlogApril 6th, 2015