Regular or Lite?

Many individuals will find WorldClock Lite suits their needs fine, just as it is.  Others
will want to upgrade to the full WorldClock program.

WorldClock Lite is intended to provide most of the features desired by the casual
user, with sufficient documentation needed to install and run it, in a package small enough
to be downloaded by modem fairly inexpensively.  To reduce size and downloading time,
WorldClock Lite comes with a much smaller, non-illustrated documentation file, and a 
smaller database of stored worldwide locations.

First of all, WorldClock Lite gives accurate times for sunrise, sunset, moonrise and 
moonset at each of the 190 locations in its database.  (Accuracy is ± 1 minute for sunrise
and sunset and ± 2 minutes for moonrise and set.)  Since WorldClock Lite does
not have the option to add your own specific location to the database, the accuracy of the
forecast sunrise/sunset and moonrise/moonset times for your specific location, will 
depend upon how near you are to the closest location stored in the program's database.
Chances are pretty good that there is a database location within 100 miles of you, if you
live in the United States.

The Earth turns one degree toward the east every four minutes.  At 38° north latitude (the 
latitude of San Francisco) one degree to the east is approximately 56 statute miles.  Thus, 
if your actual location were to be 56 miles east of San Francisco, and WorldClock Lite 
were set to San Francisco, the times reported by WorldClock Lite would be correct for 
San Francisco, but approximately four minutes later than the actual times at your location.

                To oversimplify a bit, if your location is anywhere within 100 miles 
                of the database location you have selected, the difference between the 
                actual times, and the rising and setting times forecast by WorldClock 
            Lite, will generally be eight minutes or less.  

With WorldClock Lite, you can...

• See the present pattern of daylight and nighttime over the globe.
• See the current time at any five of the 190 WorldClock database locations.
• Set the "location" of any of the five clocks by clicking on the clock, and then selecting
  the new location from a scrolling list.
• See the current time in AM/PM, 24-hour, or Universal Time format.
• See the present position of the sun over the earth.
• See the present position of the moon over the earth, and the phase of the moon.
• Determine sunrise/set, moonrise/set, twilight times, and hours of daylight for any of the 
  190 locations in the database.
• Experiment by clicking on the map to see the above information for the location clicked.
• Set the date with a clickable calendar.
• See the dates for the key moon phases - new moon, 1st quarter, full moon, and 3rd
  quarter - for the current month or any month of interest.
• See a "sundial" display for the database location currently selected.  The sundial display
  can be animated and/or frozen to display shadow conditions at any particular time for
  the database location selected. 
• Select from among 190 worldwide locations, and set your system clock.

With WorldClock, in addition, you can...

• Choose from over 340 worldwide database locations.
• Add additional database locations of your own, up to a maximum of 400 locations.
• Select the daylight savings time start/stop rule to be used by each location you add.
• Get the maximum possible accuracy for your particular location.

Profile of the WorldClock Lite user...

Works at a desktop Macintosh, located within 100 miles of one of the WorldClock Lite
database locations.

Uses WorldClock Lite primarily to see the current day/night pattern over the world, and
to see the current time at key world locations.

Occasionally needs to see the dates of key moon phases during a month, and/or to see 
the approximate times of sunrise and sunset, moonrise or moonset.

Educational user demonstrating earth-sun-moon relationships to a class.

Profile of the full WorldClock program user...

Works at a desktop Macintosh, located more than 100 miles from the nearest WorldClock
Lite database location, or uses a PowerBook from a variety of locations.

Someone who travels frequently, taking a PowerBook along.

Uses WorldClock to forecast specific solar or lunar conditions, including sun/moon
positions and shadows, at a given time.  Such a person might be a photographer, 
cinematographer, pilot, ham radio operator, boat/ship operator, or astronomer.

Someone who simply prefers to have the most accurate information available for his or her 
location.