# Common Data Types

The API types **MUST** adhere to the formats defined below:

| Data type      | Standard                                                               | Example                                   |
| -------------- | ---------------------------------------------------------------------- | ----------------------------------------- |
| Date and Time  | [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601)                     | 2017-06-21T14:07:17Z (Always use UTC)     |
| Date           | [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601)                     | 2017-06-21                                |
| Duration       | [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601)                     | P3Y6M4DT12H30M5S                          |
| Time interval  | [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601)                     | 2007-03-01T13:00:00Z/2008-05-11T15:30:00Z |
| Timestamps     | [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601)                     | 2017-01-01T12:00:00Z                      |
| Language Codes | [ISO 639](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes)       | en <-> English                            |
| Country Code   | [ISO 3166-1 alpha-2](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) | DE <-> Germany                            |
| Currency       | [ISO 4217](https://en.wikipedia.org/wiki/ISO_4217)                     | EUR <-> Euro                              |