Googled But Have Unanswered Questions - Galaxy S III Q&A, Help & Troubleshooting

Hey guys,
Just installed my first rom and my head is spinning at the unanswered questions i have.
my first question is regarding clockworkmod
if i go into "apply update from .zip..." theres an option that says "apply /sdcard/update.zip". That option was there even before i loaded a custom rom. If i clicked on that when I have a custom rom running, what exactly does it do. My understanding is that "update.zip" is from the original rom. Is that correct?
Second question
What is the difference between doing a wipe data/factory reset from CWM when compared to doing it through the settings menu?
I never make a back up because I have no issues starting over but i just realized that some roms require you to install it with a "stock device." If a rom requires a stock start, does that mean you have to odin and wipe it to the stock rom before installing that specific rom?
If a rom doesn't require you to have the stock rom, does that mean you can just flash over custom rom after custom rom?
In those situations, do you move the rom.zip to the root folder THEN go into CWM and wipe dalvik THEN choose "install zip" or is it another order?
Under mounts and storage, what does "format/system" do? is that the same as "wipe data/factory reset"?
maybe i should just go back to iphone. this is just a cluster**** of info.

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Update.zip is old stuff, as you suspected its to do with official updates. Cwm works across many devices that's why it's still there.
Your phone is divided into several partitions. They are prefixed with a / because the Linux convention treats partitions exactly the same as directories. Unless you have been living under a rock you probably know android is a fork of Linux.
/boot contains the Linux kernel
/recovery contains the recovery mode software, in your v case cwm.
/system holds the system apps and files.
/cache is similar to the swap file on a Windows pc or the /tmp directory on Linux. Dalvik cache is stored here as well although I'm not 100% site how that works. It's something to do with the java runtime.
/data is all your user settings and apps.
Factory reset wipes /data and /cache thus removing all installed apps and your account settings etc. A factory reset achieves the same thing regardless if you launch it in cwm or from the settings menu.
When changing roms you don't need to go back to stock first, it's just the way some devs have written their instructions. You should however always wipe /cache when changing roms. A full wipe is not usually required unless you are changing to a completely new base e.g. upgrading from an xxalf Rom to xxlfb you shouldn't need full wipe or going from one xxlfb Rom to another shouldn't need wipe. Changing from a Samsung based Rom to something like Cyanogenmod you should always full wipe.
Always wipe before flashing as some roms modify /data.
Sent from my GT-I9300 using Tapatalk 2

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dr.m0x said:
Update.zip is old stuff, as you suspected its to do with official updates. Cwm works across many devices that's why it's still there.
Your phone is divided into several partitions. They are prefixed with a / because the Linux convention treats partitions exactly the same as directories. Unless you have been living under a rock you probably know android is a fork of Linux.
/boot contains the Linux kernel
/recovery contains the recovery mode software, in your v case cwm.
/system holds the system apps and files.
/cache is similar to the swap file on a Windows pc or the /tmp directory on Linux. Dalvik cache is stored here as well although I'm not 100% site how that works. It's something to do with the java runtime.
/data is all your user settings and apps.
Factory reset wipes /data and /cache thus removing all installed apps and your account settings etc. A factory reset achieves the same thing regardless if you launch it in cwm or from the settings menu.
When changing roms you don't need to go back to stock first, it's just the way some devs have written their instructions. You should however always wipe /cache when changing roms. A full wipe is not usually required unless you are changing to a completely new base e.g. upgrading from an xxalf Rom to xxlfb you shouldn't need full wipe or going from one xxlfb Rom to another shouldn't need wipe. Changing from a Samsung based Rom to something like Cyanogenmod you should always full wipe.
Always wipe before flashing as some roms modify /data.
Sent from my GT-I9300 using Tapatalk 2
Click to expand...
Click to collapse
thank you for taking the time out to write that.
What is the difference between advanced restore and advanced back up against regular restore and back up (in CWM).
Also, which exactly do i have to wipe. Which cache? There are three different options i think.
Lastly, if i made a nandroid backup of the rooted stock rom in its stock form with no mods, do i still have to wipe the cache when i install a new rom?

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fruitycups said:
thank you for taking the time out to write that.
What is the difference between advanced restore and advanced back up against regular restore and back up (in CWM).
Also, which exactly do i have to wipe. Which cache? There are three different options i think.
Lastly, if i made a nandroid backup of the rooted stock rom in its stock form with no mods, do i still have to wipe the cache when i install a new rom?
Click to expand...
Click to collapse
Advanced backup and restore lets you choose which partitions to backup or restore, vs the standard option which backs up everything.
As I mentioned earlier you only need to wipe the cache. Dalvik cache is a sub directory of /cache so wiping /cache will wipe that also.
You should always wipe /cache when installing a new Rom. It doesn't affect anything from the user perspective except that first boot will be long while android rebuilds the cache. It probably isn't strictly necessary when moving to roms with the same base but can't hurt since it has no negative impact. Even factory updates wipe the cache automatically for you. Some custom roms do as well but better safe than sorry since most don't tell you either way in the description.
Sent from my GT-I9300 using Tapatalk 2