Time Zones
Time zones are an optional feature included with both Standard and Lite versions of Sugar Calendar, starting with version 2.1.0.
When enabled, this feature reveals some additional inputs on the "Add New Event" and "Edit Event" screens for setting the time zone alongside the Start and End Date and Time. You may want this if your Events are visible to an audience wider than just yourself and the time zone you are in.
It also reveals some additional user interface elements in Sugar Calendar's Admin pages to help make sense out of the various time zone offsets and calculations when you are viewing calendars and lists of events.
When not enabled (or "off") time zones are considered "floating". This means that the dates and times will always show the same values for all users, as there is no time zone information to offset them by.
Examples
1. You have a flight from New York to Los Angeles, that starts in "Eastern Time" and ends in "Pacific Time". Being able to set the time zone for both the start and end boundaries for this flight/event allows for more accurate and reliable calculations and displays as you travel between time zones yourself.
2. An online event with many individual presentations, has attendees that are virtual and viewing from any possible time zone. By setting the time zone(s) on each presentation/event, all attendees/visitors will be able to calculate the time difference between their own locations and the presentation time.
Caveats
It is possible for time zone information to appear on Events and Calendars even when the Time Zone feature is "off" or not explicitly enabled. This may happen if an event already includes time zone data, either by way of being saved previously via Sugar Calendar when the feature was previously enabled, or having been imported that way from other piece of calendar software.
Settings & Preferences
When enabled, the Time Zone setting will be used as the default for new Events when no other User Preference is set. 
Users have the ability to set their own time zone preference using the "Screen Options" tab in the upper right corner of the WordPress Admin area. When set, this preference will be taken into account when viewing Calendars and lists of Events. 
Visitor Adjustments
When enabled, and when available, this feature will try to detect the time zone that the website visitor is currently located in, and automatically change the date and time output to be correct for them where they are. This feature relies on the visitor's browser to have support enabled; if it is disabled nothing will change for them.
Because this feature is triggered dynamically with JavaScript, a small delay while the page finishes loading is normal before the dates and times are updated.
Wherever times and dates are output by Sugar Calendar, every attempt has been made (and will be made in the future) to wrap the content in a specific HTML tag designed to help computers more easily understand exactly what date, time, and time zone is being displayed.
These tags include various pieces of meta-data used by Sugar Calendar to perform the necessary functions of the application. It is recommended to take care when using WordPress hooks to filter these tags, as unexpected or unintended behavior may result from changing these values.