The /etc/localtime file is used to configure the system-wide timezone of the local system that is used by applications for presentation to the user. It should be either a symlink to or a copy of a timezone information file that contains the binary data for the configured timezone. The timezone information files are located under
/usr/share/zoneinfo/ and are named after the geographic regions and cities, such as Europe/Berlin or Etc/UTC.
The timezone identifier is extracted from the symlink target name of /etc/localtime, so it is recommended to use a symlink rather than a copy. The timezone can be changed by using the timedatectl command or by creating a new symlink to the desired timezone file123. References:
* How to Set or Change the Time Zone in Linux | Linuxize
* localtime(5) - Linux manual page - man7.org
* localtime(5) - Arch manual pages