With a Motorola, you used an exploit to install a second system and custom recovery with Safestrap.
In general, an HTC roots like a Nexus (and not surprising as HTC made the first one).
Usual steps -
1. Unlock bootloader. Only difference from Nexus is you have to get a token from HTC. Erases your data.
2. Install custom recovery. Stop here and make a full backup (nandroid).
3. Add SuperSU using custom recovery - or - use custom recovery to flash a ROM with superuser already baked in.
Up to this point, you've relied on no exploits.
And with both the Nexus and the HTC, both bootloaders will still have some partitions locked with encrypted signature security - a manufacturer's security signature is required to install into some partitions.
On an HTC, encrypted signature security protection on is called s-on.
And unlike most other devices, there are from time to time exploits to get rid of that: s-off.
And that's the Holy Grail in rooting - with s-off, you will probably never need to unroot or screw around with unknown processes again.
S-off is permanent for all normal purposes.
The Sunshine exploit let's you jump past the part where you lose everything on the unlock.
And because it's an exploit, it's subject to closure by firmware updates by HTC.
If you're in to rooting and you have an HTC and understand s-off, then you always go for it at your earliest opportunity.
I personally know of HTCs where people put this off before the next big update who a) waited a lot of months for it to reappear, b) had to physically open there phone and short something on the motherboard while running to get it, and c) never got the chance again.
If you're going to root, and just not sure when, and s-off is available to you, you go for it right away or you take your chances.
It might still be here next week. And it might not.
Hope this helps.
PS - iow, follow the Captain's advice or suffer one of my long posts.
S-on: the price is just too high.
S-off: only $25.