• Data models facilitate • Early analysis of properties, . . storage cost, querying ability, • Re-use of shared data among multiple applications • Exchange of data across organization • Conversion of data to new software/ environment • Example - Y2K crisis for year 2000 Many computer software systems were developed without welldefined data models in 1960s and 1970s. These systems used a variety of data models for representing time and date. Some of the representations used two digits to represent years. In late 1990s, people worried that the 2 digit representation of year may lead to errorneous behaviour. For example age of a person born in 1960 (as 60) in year.
