A calendar is a system of organizing days for social, religious, commercial, or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. The name given to each day is known as a date. Periods in a calendar (such as years and months) are usually, though not necessarily, synchronized with the cycle of the sun or the moon. Many civilizations and societies have devised a calendar, usually derived from other calendars on which they model their systems, suited to their particular needs.

A calendar is also a physical device (often paper). This is the most common usage of the word. Other similar types of calendars can include computerized systems, which can be set to remind the user of upcoming events and appointments.

As a subset, calendar is also used to denote a list of particular set of planned events (for example, court calendar).

The English word calendar is derived from the Latin word kalendae, which was the Latin name of the first day of every month.

• Reminders (25)

• ASP@ (11)
• PHP@ (14)

See also:

• Computers: Software: Groupware (425)
• Computers: Software: Human Resources: Appointment Scheduling (10)
• Computers: Software: Internet: Servers: Collaboration (38)
• Computers: Software: Intranet (15)

• Proverbs Web Calendar
  proverbs.biz
  Customizable web calendar developed using PHP and MySQL. Calendar is viewed in month format. Popup window details events as they are clicked on. Title and colors are customizable and the application can be modified to work with other database types.
• Brown Bear Software
  brownbearsw.com
  Provides web calendar solutions for Windows and Unix servers.
• Yahoo! Calendar
  calendar.yahoo.com
  Offers public and private event scheduling, to-do lists, weather, and integration with Microsoft Outlook and Palm devices.