title: Why are strings immutable in many programming languages?
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/93091/why-cant-strings-be-mutable-in-java-and-net">Why can&#39;t strings be mutable in Java and .NET?</a><br>
    <a href="https://stackoverflow.com/questions/2365272/why-net-string-is-immutable">Why .NET String is immutable?</a></p>
  </blockquote>
  
  <p>Several languages have chosen for this, such as C#, Java, and Python.  If it is intended to save memory or gain efficiency for operations like <em>compare</em>, what effect does it have on concatenation and other modifying operations?</p>