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Introduction to libraries"></td></tr><tr><td bgcolor="ffffff" width="15"> </td><td bgcolor="ffffff" width="12"> </td><td valign="top" align="left" bgcolor="ffffff" width="*"><p><br x="7"><table cellspacing="0" cellpadding="0" border="0"><tr><td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>What is a library?</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr> page 1 of 6</nobr></font></td></tr></table><br x="7"><br x="7"></p><font size="2" face="Verdana, Arial, Helvetica"><p>
A library is a reusable software component that saves developers
time by providing access to the code that performs a programming task. Libraries exist to assist with many different types of tasks.
</p><p>
Library design is difficult. It's easy to take an algorithm you've
written and call it a library, but it's harder to structure it in such
a way that it can fit into someone else's program and still perform the
tasks it is designed to do without interfering with the original program's
operation.
</p><p>
Most modern languages try to help the programmer create good
libraries, and the Java language is no exception. In this tutorial,
you'll learn how the Java language can help you make a good, reusable
library.
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