In computing, an attribute is an entity that defines a property of an object, element, or file. An attribute usually consists of a name and a value. Its definition can be extended by a datatype, a representation format, a default value and restrictions. For example, in computer graphics, line objects can have attributes such as thickness (with real values), color (with descriptive values such as brown or green or values defined in a certain color model, such as RGB), dashing attributes, etc. Markup languages, such as HTML and XML, use attributes to describe data and the formatting of data.
