Days, months and years are called unit of time.
We can count a year by two ways. One in the solar and other is loner. Solar is called English calendar and Lunar is called the Islamic calendar. English Calendar English calendar is calculated by the rotation of the sun. It is also called the Solar Calendar.
There are 12 months in a year. The earth complete its revolution around he sun in one year. The counting of solar year is Starts from the birth of Prophet Isa (A.S). A English month has 30 or 31 days expect the month f February. Which has 28 or 29 days? Any year who divided by 4 is called leap year.
In a leap year the month of February has 29 days. In a leap year there are 366 days otherwise 365 days in a year. The detail of solar month is as under. There have a twelve month in each year but different with days. They have started January and last month called December. Islamic Calendar In an Islamic Calendar there are also 12 months. The moon complete its revolution around the earth in one month . The counting of months of lunar year is done with references to the moon. This is why some months have 29 days and some 30 days. The counting of the years starts from the migration of the Holy Prophet (P.B.U.H) to Medina. The names of these months are as under. Same in Islamic calendar have twelve months but name are changed. They have started with Meharm and the last month zil.haj.