# Field Types
To support multiple SQL vendors (MySQL, PostgreSQL, MS-SQL, etc) Directus has a generalized set of field types to define API output (
array,json,boolean, etc) and system data (m2o,alias,group, etc).
alias– Fields that do not have corresponding column in the databasearray– Standard array format in API responsebinary– Binary strings limited by its lengthboolean–trueorfalsedatetime– A date and time in ISO format, eg:2018-09-19T14:00:43+00:00date– Date, eg:2018-09-19time– Time, eg:14:09:22file– Foreign key todirectus_files.idgroup– Groups fields together visually, children save group intodirectus_fields.grouphash– Its value gets hashed based on thehasheroption. (Default to:password_hash.PASSWORD_DEFAULT(opens new window))integer– Whole numberdecimal– Number that includes a decimaljson– Standard JSON format in API responselang– Specific to translation interfaces, this stores the language keym2o– Many-to-One Relationshipo2m– One-to-Many Relationshipslug– Removes all the special characters from another field. It will ignore the mirrored field value if the slug already has a value set.sort– System field that stores a item order within the collection itemsstatus– System field used for publishing workflowsstring– Any text or characters, limited by its lengthtranslation– Specific to translation interfaces, this is ao2mfor multi-lingual contentuuid– A Universally Unique Identifierdatetime_created– System field to track the datetime an item was created, used by revisionsdatetime_updated– System field to track the datetime an item was updated, used by revisionsuser_created– System field to track the user who created an item, used by revisionsuser_updated– System field to track the user who updated an item, used by revisions
Datatypes
When creating or updating fields you can also set a vendor-specific datatype for more granular DBA control over data storage.