Calendar and Timeline

A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months, and years.

A date is a designation of a single, specific day within such a system. Periods in a calendar are usually synchronized with the cycle of the sun and moon.

The calendar we use is a solar calendar with 12 months and 28, 30 or 31 days in each month.

• We write the date as a date, then a month, and then a year:

Date - Month - Year

Example:

2nd February 2022 written as: 02–02–2022 or 02/02/2022 or 02.02.2022

4th December 2022 written as: 04–12–2022 or 04/12/2022 or 04.12.2022

12th January 2022 written as: 12–01–2022 or 12/01/2022 or 12.01.2022

• The international standard recommends writing a date as year, then month, then the day: Year - Month – Date

Example:

In the international standard, 20th July 2022 can be written as:

2022–07–20

• Writing the dates in this way avoids confusion.

Relation Between Year, Month, Week, and Day

• A day consists of 24 hours. A day starts at the midnight 12 am and ends at the next midnight 12 am.

• So, after midnight the date also changes as another new day started.
• A week consists of 7 days. There are 4 or 5 weeks in a month.

• There are twelve months in a year. Each month has 28, 30 or 31 days.

Hence,

• 1 day = 24 hour
• 1 week = 7 days
• 1 month = 4 or 5 weeks and 1 month = 28 to 31 days
• 1 year = 365 days and One leap year = 366 days
• 1 year = 52 weeks (approximate)
• 1 year = 12 months
• February has the least number of days. In the month of February, there are 28 days generally. But in a leap year, there are 29 days in February.

Leap year

Leap years are years where an extra day is added to the end of the shortest month, February. February 29, is commonly referred to as leap day. Leap years have 366 days instead of 365 days and occur almost every four years.

Since there are 28 to 31 days in a month, then we use a simple trick to remember which month has how many days. This is called Knuckle trick.

Knuckle Trick

Other than February every month have 30 or 31 days.

One can remember the days of each month from his/her knuckle.

We will count the months in the knuckles and the hollow between two knuckles. Start counting from the knuckle of the index number with January. If a month lands on the knuckle, then it has 31 days and if a month lands on the hollow between two knuckles, then it has 30 days or 28 days (for February).

Timeline

A timeline is a list of important events arranged in the order in which they happened. Timelines are often used in history textbooks and biographies. They explained what happened during a certain period of time or to a particular person, starting with the earliest event and moving forward through time.

Example:

This is the timeline for the covid 19 pandemic from Mar 2020 To Mar 2021.