Consider a large university library. Tens of thousands of books,
periodicals, and other information resources are available for use. But
to access these resources, a categorization scheme must be developed. To
navigate this large volume of information, librarians have defined a
classification scheme that includes a library of congress classification
code, keywords, author names, and other index entries. All enable the
user to find the needed resource quickly and easily. Now,
consider a large component repository. Tens of thousands of reusable
software components reside in it. But how does a software engineer find
the one she needs? To answer this question, another question arises: How
do we describe software components in unambiguous, classifiable terms?
These are difficult questions, and no definitive answer has yet been
developed.R. S. Pressman. Software Engineering - A Practitioner's Approach, 4 edn, th New York: The McGraw-Hill Companies Inc. 1997, p. 743 (with adaptations).From the text above, it can be concluded thatit was so difficult to access reusable software that only now has an answer been found to solve this problem.