Attribute

A smallest unit of content, and the basic building block of a content type.

An attribute holds a value, which is a unit of content.

At their simoklest level, content types are a collection of attributes.

For example:

• Title
• Subtitle
• Byline
• Date Published
• Body

Attributes will usually always have a set datatype which restricts the type of value it can hold. Attributes will often have valuation rules applied, which limit the data that can be entered.

Datatypes and validation rules are slightly different. A datatype are types like text or number, whereas a validation rule is more finely grained -- for example, a number greater than 1900 but less then 2100. So, while the datatype of "number" would allow for a value of 3,000, the validation rule would prevent it.

Nomenclature varies widely. Many systems refer to an attributes as a property or field or (less commonly) a parameter. There is no standard.

Some CMS have built-in attributes which are present in all types. These are common:

• ID
• Title
• Body (longer text, often allowing rich text)
• Owner

A content type is defined by what attributes exist in addition to these.