Date and time notation in Czech Republic

In the Czech Republic exist two different standardized lines of date and time writing.

First one are Rules of Czech Orthography as mandatory for educational system (elementary schools etc.). These rules are based on traditional writing and due to teaching in schools it's widely used by common people. Date is written in "day month year" order, each part separated by space, day and month as ordinal numbers, year as cardinal (1. 12. 2009). The month can be replaced by full name in genitive case (1. prosince 2009). As archaic is considered month in roman digits (1. XII. 2009). Time of day format is dot separated hours and minutes without space (3.15). However to express time period the colon must be used (3:15).

Second line is defined by Czech State Norm (ČSN 01 6910) based on ISO standards. It accepts ISO format (2009-12-01 and 03:15) however it allows simplified traditional formatting and/or globalized formatting like leading zeros or omitted spaces (01.12.2009) too. The second norm is intended for technical devices and tabular output. However due to globalization and import of foreign goods, the time format with colon instead of period (3:15 or 03:15) is accepted and used by ordinary people more than the traditional typographical school system.

The 24-hour counting is used for official and exact purposes, the 12-hour cycle is used in daily life, especially in spoken language. The week starts on Monday.

After passing 2000 year, the year value is almost always written in full four-digit form. In spoken language, especially by elder people, years referencing to second half of 20th century are abbreviated by stripping the century digits (89 instead of 1989). Such abbreviation is usually marked up with leading apostrophe ('89) or with horizontal bar above both digits.