In a record several objects can be collected. The objects in a record are stored in record fields, and are accessed by using fieldnames. Records are like tuples (and unlike sets or sequences) in that the objects need not all be of the same kind. Though records and tuples are somewhat similar, there are several differences too. The components of tuples are indexed by integers, and every component must be defined. The fields of records are indexed by fieldnames, and it is possible for some (or all) of the fields of a record not to be assigned; in fact, a field of a record may be assigned or deleted at any time. A record must be constructed according to a pre-defined record format, whereas a tuple may be constructed without first giving the Cartesian product that is its parent, since Magma can deduce the parent from the tuple.
In the definition of a record format, each field is given a fieldname. If the field is also given a parent magma or a category, then in any record created according to this format, that field must conform to this requirement. However, if the field is not given a parent magma or category, there is no restriction on the kinds of values stored in that field; different records in the format may contain disparate values in that field. By contrast, every component of a Cartesian product is a magma, and the components of all tuples in this product must be elements of the corresponding magma.
Because of the flexibility of records, with respect to whether a field is assigned and what kind of value is stored in it, Boolean operators are not available for comparing records.