Articles About Dates (17)
![Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/istock-calendar-days.jpg?1)
The 7 Days of the Week
The 7-day week is the international standard that is used by the majority of the world. There are 52 or 53 weeks in a year, but countries vary on how they count the weeks.
![Tourists visiting the Papal Basilica of St. Peter in the Vatican City Rome, Italy - November 2015. Tourists visiting the Papal Basilica of St. Peter in the Vatican City Rome, Italy - November 14, 2015](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/italy-rome-vatican-.jpg?1)
The Gregorian Calendar
The Gregorian calendar is the internationally accepted civil calendar that was first adopted in 1582.
![The ancient city of Pompeii, Italy was founded around 600-700 BCE and destroyed by a volcanic eruption of Mount Vesuvius in 79 CE. Tourists visit the ruins of the ancient city of Pompeii, Italy.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/ruins-pompeii-italy-volcano.jpg?1)
What Do CE and BCE Mean?
CE is an abbreviation for Common Era and BCE is short for Before Common Era.
![An Easter Sunday date in the calendar Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/easter-date-calendar.jpg?1)
Calculating the Easter Date
The date of Easter Day depends on age-old approximations of the Full Moon and the March equinox.
![Today, women can ask a man to marry her. Today, women can ask a man to marry her.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/sadie-hawkins-day-fun.jpg?1)
Leap Day February 29
When is the next Leap Year? A Leap Year consists of 366 days – not 365 – where February 29 is added as an extra day at the end of February.
![A palindrome reads the same backwards and forwards, like 'BOB' Palindrome](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/palindrome-bob.png?1)
Palindrome Day
A Palindrome Day happens when the day’s date can be read the same way backward and forward. The dates are similar to word palindromes in that they are reversible. Depending on the date format Palindrome Days can be rare.
![The statue of the lion of Babylon was discovered in 1876. It is considered among the most important symbols of Babylon. 3 men next to the black basalt statue of the lion of Babylon which depicts a lion standing above a laying human in today's Iraq. March 20, 2015.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/statue-lion-babylon-iraq.jpg?1)
Why Does a Week Have 7 Days?
It's Monday, you have to wait 5 days till the weekend. Why does a week have 7 days, and why in that order? Thank the Moon and an ancient people in today's Iraq.
![Fireworks at night over a bridge. Boats on the river under the bridge.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/fireworks-night-sydney.jpg?2)
When Did the 21st Century Start?
When did the 3rd millennium and 21st century begin: on New Year's Day 2000 or 2001? Do we count from year 1 or year 0 AD? What century are we in?
![Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/special-date-11-11-11.png?1)
11/11/11 – a date with a special meaning?
The meaning of dates, such as 11/11/11, is becoming more popular since the start of the new millennium.
![30 February Sweden Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/30-feb-sweden.png?1)
February 30
February 30 actually existed at least twice in the past, according to historical records.
![Illustration of black grinning cat with person's legs next to it. Blue background and Friday the 13th written on the top left of the image.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/friday13.png?1)
Friday the 13th Facts
13 facts about Friday the 13th, the unluckiest day in the Gregorian calendar.
![Several pairs of colorful fashionable ladies gloves on display.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/pair-gloves-leap-day-refusal.jpg?1)
Leap Day Customs
Learn more about Leap Day traditions, superstitions and folklore.
![Calendar page](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/leap-year-capital.jpg?1)
The Doomsday Rule
Some dates fall on the same weekday every year. Use this knowledge to calculate the weekday of any given date in your head.
![Special dates in the Gregorian Calendar. Special dates in the Gregorian Calendar.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/special-dates-typography.jpg?1)
Special Calendar Dates
Learn more about numerically unique calendar dates such as sequential dates, same number dates, and palindrome (reversible) dates
![Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/special-date-12-12-12.png?1)
12/12/12 - Special Date Pattern
December 12, 2012 or 12-12-12 was the last date of its kind - when all three numericals in a date were the same - for 88 years. The next time this will happen is on January 1, 2101, or 01-01-01.
![Illustration image](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/long-weekend.png?1)
When Is the Next Long Weekend?
A long weekend lasts at least three days because a Monday or a Friday is a (bank) holiday. A four-day bridge weekend is when a Thursday or Tuesday is a holiday and you also have the bridge day off to join it with the weekend.
![People watching fireworks above a mountain village.](http://webcf.waybackmachine.org/web/20210812041356im_/https://c.tadst.com/gfx/150x84/new-year-saas-fee.jpg?1)
When Do Decades Start?
Did the year 2020 mark the beginning of a new decade, or did the twenties begin on January 1, 2021?