The .ttf extension indicates it is a TrueType Font , a standard developed by Apple and Microsoft in the late 1980s to ensure consistent rendering across different screens and printers.
The default Android font, offering a similar clean feel. HelveticaNeue-Regular.ttf
Developers often reference this file in CSS using the @font-face rule to ensure custom fonts load correctly on platforms like Salesforce or Flutter. HelveticaNeue-Regular.ttf