A Binary is a field for storing binary data, such as images.

A Boolean is a field for storing true/false values.

A Char is a field for storing short text.

A Date is a field for storing dates without time.

A DateTime is a field for storing dates with time.

A Float is a field for storing decimal numbers.

An HTML is a field for storing HTML formatted strings.

An Integer is a field for storing non decimal numbers.

A Many2Many is a field for storing many-to-many relations.

A Many2One is a field for storing many-to-one relations, i.e.

A One2Many is a field for storing one-to-many relations.

A One2One is a field for storing one-to-one relations, i.e.

A Rev2One is a field for storing reverse one-to-one relations, i.e.

A Selection is a field for storing a value from a preset list.

A Text is a field for storing long text.

A FieldDefinition is a struct that declares a new field in a fields collection;.