2.3.1. How should client applications present a choice of time zones to users?
2.3.1.1.
Use TZDATA database (a.k.a. Olson Database, “America/New_York”) names.
2.3.1.2.
Use a GMT Offset scheme (“GMT+2, Cairo”…).
2.3.1.3.
Use common name presentation (EST5EDT, PST8PDT…).
2.3.1.4.
Additionally, a “clickable” world map is often used.