Bricking - To take all function away from an iPhone or iPod Touch hence rendering it as nothing more than a shiny "brick". Sometimes firmware updates cause temporary bricking off the iPhone, for updates often fail or come with bugs. It is for this reason that you should frequently back up your iPhone.
Baseband - The Baseband handles all things "cell phone" related. In order to unlock the iPhone to use it with non-official carriers the Baseband is what must be hacked. An iPod Touch lacks the "Baseband" half, hence its inability to execute phone calls.
Bluetooth - is a proprietary open wireless technology standard for exchanging data over short distances (using short wavelength radio transmissions) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security.