How did the calendar take birth?

Since the beginning of civilisation, man has been observing sunrise and sunset, and experiencing the occurrence of day and night. He also observed the various phases of moon, from one full moon to the next, and the cyclic change in the seasons. He realised that crops did not grow at all times nor was the temperature uniform throughout the year. With fast developing science, man understood things more. The time taken by Earth to complete one rotation on its axis came to be known as day and night. The time taken by the moon to complete one revolution around Earth was called a month, and the time taken by Earth to complete one revolution around the Sun as one year, which comprised of 365 days. The Egyptians were the first to have a calendar of one whole year, comprising of 12 months, each month of 30 days. Five extra days were added at the end of the year, thus making a total of 365 days. The people of Greece however, used the lunar calendar. The Roman ruler Julius Caesar took a major step in 46 B.C. He sought the help of the Greek astronomer Sosigenes, to adopt a uniform calendar. He finally accepted the calendar based on the time taken by Earth to complete one revolution around the Sun, which is 365¼ days; this is known as the solar calendar. The extra quarter of a day caused confusion, so Caesar ordered that the year 46 B.C. should have 445 days, so as to catch up. The astronomers of Caesar finally adopted a year consisting of 365 days, and every fourth year had 366 days, so that one-fourth of a day left out every year was compensated in the fourth year. This fourth year was called the ‘leap year’. Any year divisible by the number 4 was taken to be a leap year. 365 days of a year were divided into twelve months. The months January, March, May, July, August, October and December consisted of 31 days each, while April, June, September and November consisted of 30 days each. The month of February consisted of 28 days, whereas, in the leap year, it would have 29 days. This calendar continued for 1600 years. Subsequently, an error of 10 days was detected in these calculations, because the Earth actually takes 365.2422 days to complete one revolution round the Sun, making a difference of 7.8 days over a period of 1000 years. In 1582, Pope Gregory XIII took a decision to drop ten days from the year 1582, and for future accuracy, he ordered that a leap year should be skipped in the last year of every century unless it is divisible by 400. So 1700, 1800 and 1900 were not leap years, but the year 2000 was a leap year, with February having 29 days. This was called the Gregorian calendar and is in use all over the world, even today. The second calendar in use is the lunar calendar, which is based on time taken by the moon to complete one revolution around the Earth, which is 29½ days. The lunar year consists of 354 days (29½ x 12), which is less than the solar year by 11 days, and this makes a difference of 33 days every three years. This difference is resolved by having 13 months after every three lunar years. This additional one-month is called ‘Malmas’ in Hindi. To make up of the days of the month, the actual numbering of the lunar days is advanced or deferred for the necessary adjustment. On March 22, 1957, the Government of India introduced the Shaka calendar based on the lunar system as the official calendar. The Shaka era is behind the Christian era by 78 years. In addition to these two calendars, some countries have other kinds of calendars also, which are used for the religious and other requirements of those countries. You have already read that while making the calendar, the 365 days of a normal year were divided into 12 months. These months have been named as January, February, March, April, May, June, July, August, September, October, November and December. Do you know how did they get these names? January is the first month of the year. Its name originated from Janus, the name of a Roman god. The Romans think that this god has two faces — one for looking into the past and the other into the future. February is named after the Roman festival Februo. Mars was the Roman god of war. March is named after him. April is probably derived from the Latin word aperire, which means ‘to open’. Since the spring season falls in this month and there is blossoming in trees and plants, this month has been named April. The word May is derived from the Roman goddess Maia’s name. The origin of June is not definitely known but probably this has been derived from the name of Juno — the Queen of Heavens. July is named after Julius Caesar, who was born in this month. He was the first man who made significant contributions to the development of the modern calendar. August is named after Augustus Caesar of Rome, who won many battles in this month. September finds its origin in the Latin word ‘Septem’ meaning ‘seventh’. This was the seventh month in the old Roman calendar. October comes from the Roman word ‘octo’ meaning eight. In the old Roman calendar, this was the eighth month. November originates from the Latin word ‘Novem’, meaning nine. This was the ninth month in the old Roman calendar. December is derived from the Latin word ‘Decem’, meaning tenth. This was the tenth month in the old Roman calendar