A calendar is one of the important tools that we use in our everyday lives. A calendar helps in managing our time by allowing us to keep track of the days, weeks, months, and years and thus helps us time ourselves. A calendar has many components like months, leap years, weeks, days of weeks, etc. Reading a calendar is one of the important skills that everyone should have. Let’s learn about a calendar and the terms related to it.

## What is a Calendar?

A calendar is a system for dividing time over extended periods, such as days, months, or years and arranging such divisions in a definite order. A calendar is convenient for regulating our life and religious observances and for historical and scientific purposes.

The word is derived from the Latin calendarium, meaning ‘interest register’ or ‘account book’, itself a derivation from calendae (or kalendae), the first day of the month in the Roman republican calendar, the day on which future market days, feasts, and other occasions were proclaimed.

## Parts of a Calendar

A modern calendar normal year of $365$ days or a leap year of $366$ days is divided into $12$ months. The names of the months and the order in which they appear in a calendar are:

The month names are after Roman gods, but also have historical figures and Latin terms.

Each of the months has a fixed number of days, except February which has $28$ days in a normal year and $29$ days in a leap year.

A quick way to remember the number of days in a month.

Further months are divided into weeks.

• Each week has $7$ days
• Each month has $4$ complete weeks and
• $1$ extra day when the number of days is $29$
• $2$ extra days when the number of days is $30$
• $3$ extra days when the number of days is $31$
• Each year has $52$ complete weeks and
• $1$ day in normal years
• $2$ days in leap years

The names of the days of a week and the order in which they appear in a calendar are:

By reading a calendar, you can know about the current year, month, and day. You can keep yourself aware of and prepared for future events and their respective dates accordingly. Thus, you can keep track of the days, weeks, months, and years.

Suppose you want to know the day on which Independence Day will fall in the year $2022$.

• Open the calendar for the year $2022$.
• Open the August page.
• Mark August $15$.
• Following the column upwards you can see that Independence Day is on Monday.

## What is a Leap Year?

As mentioned above a leap year has $366$ days. What does a leap year mean?

A leap year is a year when $1$ extra day, referred to as a leap day(February $29$) is added to the shortest month, February. It is done to keep our calendar in alignment with the Earth’s revolutions around the Sun. The Earth takes approximately $365.242189$ days which is equivalent to $365$ days, $5$ hours, $48$ minutes, and $45$ seconds – to complete one revolution around the Sun referred to as a tropical year.

A leap year has 366 days instead of the usual 365 days and occurs almost every four years.

Note:

The actual time Earth takes to complete one revolution = $365$ days, $5$ hours, $48$ minutes, and $45$ seconds

Number of days in a normal year = $365$ days

Extra time left = $5$ hours, $48$ minutes, and $45$ seconds = $0.242189$ days

Extra time accumulated in $4$ years = $0.242189 \times 4 = 0.968756 \approx1$ day

## How To Check For a Leap Year?

To check for a leap year divide the year by $4$. If it is completely divisible by $4$, it is a leap year. For example, $2020$ is divisible by $4$, thus it is a leap year with a February of $29$ days.

But there is an exception to this rule and that is in a century year.

Century years like $600$, $900$, $1300$, $2000$, and many like these need to be divided by $400$ to check whether they are leap years or not. For example, a century year like $2000$ is divisible by $400$, so it is a leap year. However, a century year like $1300$ is not divisible by $400$, thus it is not a leap year, even though it is divisible by $4$.

## Conclusion

A calendar is a chart or series of pages that shows the days, weeks, and months of a particular year. The complete year is divided into $12$ months and $52$ complete weeks, where a week is a period of $7$ days. A normal year has $365$ days whereas a leap year has $366$ days. Reading a calendar is one of the important skills one should have as it helps in time management.

## Practice Problems

State True or False

• There are $7$ months in a year
• There are $12$ months in a year
• There are $7$ days in a week
• There are $10$ days in a week
• The number of having $30$ days is greater than the number of months having $31$ days
• The number of having $31$ days is greater than the number of months having $30$ days
• To check for a leap year you divide it by $400$
• To check for a leap year you divide it by $4$
• To check for a century leap year you divide it by $400$
• To check for a century leap year you divide it by $4$
• There are $50$ complete weeks in a year
• There are $52$ complete weeks in a year
• When the number of days in a normal year is divided by $7$, $1$ day is left
• When the number of days in a normal year is divided by $7$, $2$ days are left
• When the number of days in a leap year is divided by $7$, $1$ day is left
• When the number of days in a leap year is divided by $7$, $2$ days are left

## FAQs

### What does the term calendar mean?

A calendar is a chart or series of pages that shows the days, weeks, and months of a particular year. The word is derived from the Latin calendarium, meaning ‘interest register’ or ‘account book’.

### What is the purpose of a calendar?

Calendars are useful tools for keeping track of upcoming meetings, deadlines, and milestones. They can help you visualize your schedule and remind you of important events, such as holidays and vacation time.

### How many days are there in a year?

There are $365$ days in a normal year and $366$ days in a leap year which comes after every $4$ year.

### What are the calendar months named after?

The first calendar, the Roman year calendar, which was ascribed to the legendary king Romulus, had ten months. The king named the first month, Martius, after his own father, Mars, the god of war. The months-September, October, November, and December are named after Roman numbers $7$, $8$, $9$, and $10$, which were originally the seventh, eighth, ninth, and tenth months of the Roman year. The months- July and August were renamed after Roman rulers, they were called Quintilis and Sextilis, which meant fifth and sixth months.