What do the terms "BL", "AP", "CP", and "CSC" mean in Odin? I'm trying to Use Odin to download a OS to my phone (Trying to put Raspbian. Raspbian runs on the raspberry pi which has an ARM processor my android phone also has one so hopefully it'l work.)
(does something like an ISO file work? i dunno i'm gonna try and see) 

when i use Odin i see these file types "BL" "AP" "CP" "CSC" what are they??

i have no idea but i really want to know and i want to know if my android phone has something like a BIOS where i can chose to boot from a USB flash drive(this might sound really silly.)

my phone has USB-OTG support but if it depends on some sort of drivers will they work in a bios (if android phones have one)please help!! 

oh and ive already rooted my phone.
CSC (Consumer Software Customization): It is specific to geographical region and carriers. It contains the software packages specific to that region, carrier branding and APN setting.
PIT (Partition Information Table): You only need it if you screw up your partition table or if the firmware specifically requires it because of a change in the partition table layout.
BL (Bootloader): As its name implies, this option is used to flash the Bootloader of the device.
AP (Application Processor or PDA): Android.
CP (Core Processor): We call it Modem.