It essentially replaces the touchwiz skin and operating system. This is how some phones are able to get ice cream sandwich or other variants of android before the manufacturer releases it.
Also roms add tweaks to performance and the user interface. Some roms allow you to overclock your phone and improve battery life.
There are skins you can get with an app called 'launcher pro' but it is limited to how much it actually changes the UI. Though there are some pretty good skins out there for it.
If you really want a major UI change and change to some of the functionality of your phone you do need to download a custom rom.
I like sticking with SAMSUNG'S ROM mainly because I haven't found a third party rom that has as good of a camera application.
Originally Posted by dustin4vn
I'm new to android, just got the skyrocket, a day ago xD
what I'm able to do within that 24 hrs.
get free games
do some battery tweaks
rooted my phone
do some major clean up of junk att put on there.
---------------------- yes I'm a geek
now I want to know what does flashing roms do?
as far as my knowledge go, flashing roms simply install a custom or new firmware same as installing a "jailbreaked ios firmware" on an iphone.
So far, i'm liking the preinstall rom that goes with the skyrocket.
can you tell me what is the best rom available and how does it compare to the stock one?