Its allows for more control than BASH does.
Note: this is an old post from 2012 which I've possibly pasted before...
Unlike Bradley Kuhn though, a good part of my house was paid for by programming in COBOL coding in a BANK, & government.
Another link I'm providing is for 'Picking Up Perl'
which is a tutorial for coding in PERL.
If you're not familiar with awk/sed/regex's and not an old unix-salt?, I'd suggest learning PYTHON anyway; look for ''Dive into Python" or one of the other free books (for download) you can learn from.