Second option of material design inputs - a so called filled form controls. Filled text fields have more visual emphasis than outlined text fields, making them stand out when surrounded by other content and components. Both types of text fields provide the same functionality, so the type of text field you use can depend on style alone. Choose the type that: 1) Works best with your app’s visual style; 2) Best accommodates the goals of your UI; 3) Is most distinct from other components (like buttons) and surrounding content.