Re: The Android Dictionary (aka "What the hell are they talking a
HBOOT
usage – 1. HBOOT is most commonly known to the Android phone community as the first stage before the phone goes through its boot cycle. In a boot control scenario, the HBOOT provides an avenue of choice between functions up to and including a standard boot. Other choices may be things such as recovery branch, or factory reset.
2. HBOOT also serves as a gatekeeper for software updates to the device. The HBOOT commonly uses encryption technology that will check to see if the package being written is "signed." This function is often referred to as "locked." In any event, the HBOOT is a critical component. Without it, a device simply will not work.
Pasted from <http://wikibin.org/articles/hboot.html>
3. HTC's proprietary version of a bootloader. It has a few bells in it not found in many other android bootloaders such as the ability to auto-flash zip files from the sd card if they are specifically named to to a particular string recognized only by that version of hboot. Kind of a cool "get out of jail" feature, but it comes with a price...a security flag referred to as s-on.
Pasted from <http://androidforums.com/rezound-all-things-root/568278-confused-htc-terminology.html>
synonyms – bootloader
S-Off/S-On
usage – 1. S-Off/S-On means that the NAND portion of the device is unlocked and can be written to. The default setting for HTC’s devices is S-ON, which means that neither can you access certain areas of the system nor can you guarantee a permanent root. Furthermore, signature check for firmware images is also ensured by the S-ON flag.
Pasted from <http://www.addictivetips.com/mobile/what-is-s-off-how-to-gain-it-on-htc-android-phones-with-unrevoked-forever/>
2. HTC's proprietary
3. S-Off disables the security check that runs on a normal, s-on scenario. That check is looking for an official signature on any files that would be loaded through the bootloader. s-off bypasses that check so it's both more dangerous (because most any file can be rammed through by the end user) but it also allows much more flexibility that can be used for positive root means like loading unsigned custom recoveries, boot img's, radios and other hboot versions. Radios/HBOOT versions may be leaked or extracted from an officially signed file (still viewed as not legit by the security flag) so they can be loaded individually without loading the entire update. This sort of thing can come in handy for rooted users who want to update the nuts and bolts of their phone while staying on custom roms the whole time. So in a nutshell, being S-Off can be compared to a fully unlocked bootloader on some other Android devices.