The term "date" has many different meanings, but in the context of time, the date refers to the calendar date. The Gregorian calendar is the standard calendar used around the world, but there are many others.

There are also numerous date formats used worldwide, but most systems include three parts: the day, month, and year. The year is usually counted relative to some specific starting point (called an epoch), the most common being the birth of Jesus. This is the epoch used for the Gregorian calendar.

Common date formats

Month/day/year (MDY) - This format is one of the most common formats used in the United States, along with the YMD format. It is a format that is used in some other parts of the world as well, but mostly in the US. Examples include:

Day/month/year (DMY) - This is the format used by the largest number of people around the world. Examples include:

Year/month/day (YMD) - This format is used in much of the world, more as a secondary rather than primary format. Examples include:

The third format, YYYY-MM-DD is actually the international standard and is meant to ensure accuracy. Some countries have adopted this as the only official date format, though many countries around the world may unofficially use other formats.

Below is a color-coded map of the world showing which countries use which formats.

Color Format(s) Total population (in millions)
Cyan DMY 2,871
Yellow YMD 1,678
Magenta MDY 0.55
Green DMY, YMD 2,391
Blue DMY, MDY 171
Red MDY, YMD 329
Grey MDY, YMD, DMY 140