Re: How to Root HTC Evo 4G LTE
1. Superuser is the root. Its access to the root permissions of the operating system. Without that, you have no root.
2. Busybox is an app that allows additional commands at the root of the operating system, required by many root apps. Downloadable from the markets or installed via Titanium Backup.
I highly recommend reading through the Evo4G rooting section and knowing exactly what you are doing (and why) before rooting. And don't accept an OTA update if you are rooted. I also highly recommend making a nandroid backup before deleting anything.