The previous version of the standard, TBX version 2.0, was published in 2008. TBX version 3.0 was under development for a number of years and was published as ISO 30042:2019
TBX is expressed as an XML file. In TBX 2.0, the root element of the file was ‘martif’. Whenever you receive a TBX file, please check the value of the type attribute on the root element. If the root element is <martif type=′TBX′ xml:lang=′en′>, then you are looking at an obsolete TBX version 2.0 file.
In contrast, the root element of a TBX version 3.0 file is ‘tbx’ and will contain a link to the TBX 3.0 xmlns, e.g.:
<tbx xmlns:tbx3=′urn:iso:std:iso:30042:ed-2′ type=′TBX-Sample′ style=′dca′ xml:lang=′en′>
A major difference between TBX2 and TBX-3 is that TBX3 is much more flexible in that in accommodates different dialects reflecting specialized data models.
Check the Reference Link table to locate other references cited in the TBX standard.
The Data Category Registry
Part of the new TBX standard lists or refers to a master data category list, the Data Category Repository (DCR), which is configured according to ISO 12620. The DCR lists a wide selection of data categories that can be included in a TBX file. Earlier versions of TBX referred to a TBX Default list. This name has been discontinued under the new standard. There may still be mentions of TBX Default in external references. Such references should be understood to refer to the DCR website..
Each dialect is defined as a set of one or more modules. Each module establishes which data categories are allowed at which levels in the TBX 3.0 data model and with what values.
You can find more information on the dialects page.