hey guys wassup whoa such a long time sorry i couldn't post anything awesome as i was busy with my life and some major up downs. ok so now i got a galaxy Y for testing purposes and i was just messing with the phone and the best way of messing is installing different roms and etc.
So i start with the basics, the kernel is the basic part of every working computer or handheld device on earth. It is the bridge between hardware and software and its installed on rom that can be changed or erased but with some proper procedure. Android truely shares the same kernel as of what we have in linux for desktop but with some modifications So if you see this diagram you will know how critical a kernel is....
Ok how does a kernel looks like a general question comes to our mind its in .img format and contains main kernel file and boot kernel image and other drivers. So there are lots of kernel available in market which have different types of specialities some are stable, some are exprimental etc. So now comes the system apps and lots and lots of configuration files like audio bluetooth,wifi, camera, etc do not mess with these files until u are sure what are you doing. Remember all mods or custom roms do not come with custom kernel, it depends on the developer that he wants to use stock (company default) rom or a custom rom for his own. Now there are 2 ways to flash your phone to use a custom rom either with PC that is odin mode or either with clockworkmod commonly called as cwm. the basic difference between odin flashes and cwm is that, that odin uses a pc for flashing while. cwm method uses a zip file and only phone in recovery mode
the main differences are as follows.
Odin flashes are safer compared to CWM flashes in so much as they are a raw device dump with no intervention in between. Its just a basic read/write operation. CWM operations must call the current kernel in order to perform the tasks (which is why the brick bug emerges not by flashing an affected kernel, but using CWM with it afterwards). So although a CWM flash is still fundamentally an I/O process, the currently installed kernel plays its part in order to do so.
Only real danger with Odin flashes is power supply, so if you have a power cut in the middle of a flash, there is a good chance you might not ever get your device back up and running, especially if it was during a flash of the boot loader).
the firmwares is in .zip for CWM only. and for Odin/Mobile Odin files are in
.tar or .md5 (or .smd) format (other formats for other types of flash eg. .bin, .pit, .xml).
xda-developers is the best forum ever for android hacks,mods custom roms, etc
So this is pretty much for now
for more information you can read this article on android forums