A calendar date is a reference to a particular day represented within a calendar system. The calendar date allows the specific day to be identified. The number of days between two dates may be calculated. For example, "25 January 2025" is ten days after "15 January 2025". The date of a particular event depends on the observed time zone. For example, the air attack on Pearl Harbor that began at 7:48 a.m. Hawaiian time on 7 December 1941 took place at 3:18 a.m. Japan Standard Time, 8 December in Japan.
ISO 8601 is an international standard covering the worldwide exchange and communication of date and time-related data. It is maintained by the International Organization for Standardization (ISO) and was first published in 1988, with updates in 1991, 2000, 2004, and 2019, and an amendment in 2022. The standard provides a well-defined, unambiguous method of representing calendar dates and times in worldwide communications, especially to avoid misinterpreting numeric dates and times when such data is transferred between countries with different conventions for writing numeric dates and times.
A timestamp is a sequence of characters or encoded information identifying when a certain event occurred, usually giving date and time of day, sometimes accurate to a small fraction of a second. Timestamps do not have to be based on some absolute notion of time, however. They can have any epoch, can be relative to any arbitrary time, such as the power-on time of a system, or to some arbitrary time in the past.
In the Philippines, Christmas is a major annual celebration, as in most countries of the Christian world. It is celebrated as a public holiday in the country on December 25, concurrent with other countries.
Philippine Standard Time, also known as Philippine Time (PHT), is the official name for the time zone used in the Philippines. The country only uses a single time zone, at an offset of UTC+08:00, but has used daylight saving time for brief periods in the 20th century until July 28, 1990.
Different conventions exist around the world for date and time representation, both written and spoken.
"Sa Aking Mga Kabatà" is a poem about the love of one's native language written in Tagalog. It is widely attributed to the Filipino national hero José Rizal, who supposedly wrote it in 1868 at the age of eight. There is not enough evidence, however, to support authorship by Rizal and several historians now believe it to be a hoax.
Date and time notation in Canada combines conventions from the United Kingdom, conventions from the United States, and conventions from France, often creating confusion. The Government of Canada specifies the ISO 8601 format for all-numeric dates. It recommends writing the time using the 24-hour clock (17:59) for maximum clarity in both Canadian English and Canadian French, but also allows the 12-hour clock (5:59 p.m.) in English.
Date and time notation in the United States differs from that used in nearly all other countries. It is inherited from one historical branch of conventions from the United Kingdom. American styles of notation have also influenced customs of date notation in Canada, creating confusion in international commerce.
Date and time notation in Hungary has several conventions.
In Spain, date notation follows the DD/MM/YYYY format. Time notation depends on the level of formality and varies in written and spoken formats. Official time is given using the 24-hour clock, and the 12-hour clock is often used in informal speech.
The European Committee for Standardization (CEN) and (CENELEC) adopted ISO 8601 with EN 28601, now EN ISO 8601. As a European Norm, CEN and CENELEC member states are obligated to adopt the standard as national standard without alterations as well.
In Turkey, the little endian date format is used, and 24-hour clock is more common than 12-hour clock system.
In Cyprus the all-numeric form for dates is in the little endianness order of "day month year". Years are written with either 2 or 4 digits. For example, either 24/5/2004 or 24/5/04. In the Turkish occupied part in Northern Cyprus, the traditional all-numeric form of writing Gregorian dates is the little-endian day.month.year order, using a dot on the line as the separator.
Thailand has adopted ISO 8601 under national standard: TIS 1111:2535 in 1992. However, Thai date and time notation reflects the country’s cultural development through the years used. The formal date format is D/M/YYYY format (1/6/2568), nowadays using the Buddhist Era (BE). The full date format is day-month-year format which is written in Thai. While a 24-hour system is common for official use, colloquially, a 12-hour format with terms like "morning" and "night", etc., or a modified six-hour format is used.
Date and time notation in Vietnam describes methods of expressing date and time used in Vietnam.
Date and time notation in New Zealand most commonly records the date using the day-month-year format, while the ISO 8601 format (2025-01-28) is increasingly used for all-numeric dates, such as date of birth. The time can be written using either the 12-hour clock or the 24-hour clock (11:42).
