PEAR is the PHP Extension and Application Repository.  It’s basically an add-on to PHP that has a bunch of frameworks that are available.  You can read more about it at the official site. Getting PEAR onto my system was not obvious.  I came across two articles that helped quite a bit:

Although I had WampServer running, there was no trace of PEAR to be found.  I figured out that there was a bug report in for the missing PEAR file.  As a result, I downloaded the PEAR file from the official site, copied it into my WampServer installation to get going.  From there, the referenced articles above walked me through the rest – including adding to the system EVs.