The most basic logical data element is the character, which consists of a single alphabetic, numeric, or other symbol. One might argue that the bit or byte is a more elementary data element, but we should remember that those terms refer to the physical storage elements provided by the computer hardware.
Field
The next higher level of data is the field, or data item. A field consists of a grouping of related characters. For example, the grouping of alphabetic characters in a person’s name may form a name field (or typically, last name, first name, and middle initial fields), and the grouping of numbers in a sales amount forms a sales amount field.
Specifically, a data field represents an attribute (a characteristic or quality) of some entity (object, person, place, or event). For example, an employee’s salary is an attribute that is a typical data field used to describe an entity who is an employee of a business.
Record All of the fields used to describe the attributes of an entity are grouped to form a record. Thus, a record represents a collection of attributes that describe an entity. An example is a person’s payroll record, which consists of data fields describing attributes such as the person’s name, Social Security number, and rate of pay.
File
A group of related records is a data file, or table. Thus, an employee file would contain the records of the employees of a firm. Files are frequently classified by the application for which they are primarily used, such as a payroll file or an inventory file, or the type of data they contain, such as a document file or a graphical image file.
Database
A database is an integrated collection of logically related data elements. A database consolidates records previously stored in separate files into a common pool of data elements that provides data for many applications. The data stored in a database are independent of the application programs using them and of the type of storage devices on