A ‘Data Item’ refers to a single unit of values. E.g. Roll Number, Name, Date of Birth, Age etc.

There are two types of data items. These are-

1. Group Items

2. Elementary Items

1. Group Items- Data items that can be divided into sub-items are called ‘Group Items’. E.g. the name of a person is a group item because it can be divided into three sub-items: First Name, Middle Initial and Last Name. Other examples are: Address, Date, Qualification, Salary etc.

2. Elementary Items- Data items that cannot be divided into sub-items are called ‘Elementary Items’. E.g. the roll number of a student is an elementary item because it cannot be divided further into sub-items. Other examples are: Marks, Age etc.