Basic Terminology

 Data − Data are values or set of values.

Data Item − Data item refers to single unit of values.

Group Items − Data items that are divided into sub items are called as Group Items.

Elementary Items − Data items that cannot be divided are called as Elementary Items.

Attribute and Entity − An entity is that which contains certain attributes or properties, which may be

assigned values.

Entity Set − Entities of similar attributes form an entity set.

Field − Field is a single elementary unit of information representing an attribute of an entity.

Record − Record is a collection of field values of a given entity.

File − File is a collection of records of the entities in a given entity set.