Time Zones aka Timezones for Google Apps Script (GAS)

Date & Time

Date and Time are key to software development tasks such as automation or workflows. From a software point of view, they are different than normal-time or human-time. And it is important to understand how they are defined.

Specifically: a "date" in code or a "date" in software is a number. This number represents the milliseconds since 1 January 1970. This date (January 1, 1970 UTC) is also known as UNIX Epoch Time or UNIX Time. Most software developers refer to any date as a "unix time stamp" or "timestamp."

All dates and all times are converted from timestamp to human-time. To assist conversion, software developers follow the Simple Date Format. And they must account for local times zones. These zones are in Coordinated Universal Time (UTC) or Greenwich Mean Time.

Common Time zones

A list of common time zones, in GMT order, follows :
References: Date and Number Formats, Google Apps Script (GAS), Utilities.formatDate().