Higher-order Perl

Most Perl programmers, including the inventor of Perl, were originally trained as C and UNIX programmers. So the Perl programs that they write bear a strong resemblance to C programs. But Perl incorporates many features that have their roots in non-C programming languages such as LISP. These advanced features are not well understood and are rarely used by most Perl programmers, but they are very powerful. They can automate tasks in everyday programming that are difficult to solve any other way, and also serve as an introduction to the techniques of functional programming for those who have not.