Every profession or pastime creates its own own particular jargon for explaining complex concepts in an understandable manner, and the Android world is no exception.
This article is for you if you’ve googled a problem with your Android smartphone or tablet and came across terms like “rooting,” “flashing a custom ROM,” “unlocking the SIM,” or anything similar that you didn’t understand.
This article is a reference for the novice who wants to learn about all the terminology behind our Android nerdiness because Android experts presumably already know what these phrases represent.
Getting access to the system files on your Android device is what it means to root your phone. No Android device comes pre-rooted by default. Therefore, it is probably not rooted if you recently purchased an Android device and did nothing to it.
Manufacturers take this action because allowing everyone root access would cause several issues. You can access files on your device that, if deleted or altered improperly, could damage it if you have root access.
But many people still decide to root their devices because it enables them to make a lot of pretty fascinating adjustments if they know what they’re doing. It should be noted that rooting an Android device would void the warranty.
How you root your device is different for every single model. For some devices, this can prove to be a difficult process involving circumventing the manufacturer’s safety precautions. For others, it can be as simple as plugging your phone into your computer and pressing a button. You can always check out the XDA forums for instructions for your specific device.
You won’t instantly notice any significant changes after your device has been rooted. The excitement is in what you can do with a rooted device. Then, you may utilize root-required apps, flash custom ROMs, modify specific features of your phone, and more—which we’ll go over in more detail later.
For instance, when unrooted, you can remove some bloatware, but rooting your device and using Titanium Backup or a root uninstaller are required to completely remove it.
Unlocking is a confusing term because there are different things you could unlock.
A device that has been network/SIM locked was typically purchased through a carrier or for a certain carrier at a discounted price. That phone is then locked by the carrier so that you can only use it with them.
However, if you pay off the phone and decide to switch carriers, the carrier is obligated by law to provide you with the unlock code (at least in the US and the EU). To obtain the code, simply get in touch with your current carrier.
Sometimes, unlocking your device gets more complicated than that, so we have a guide to SIM unlocking. Other times, you buy your phone unsubsidized and unlocked, meaning you can already use it with any carrier.
The bootloader is a piece of software that runs every time you switch on your Android phone, and it is usually locked by the manufacturers. With a locked bootloader, you can’t root your device. Instructions for unlocking your bootloader are found within the instructions for rooting your device.
Read-Only Memory is referred to as ROM, however the term is somewhat misleading today because it has nothing to do with it. A ROM is essentially the software that runs on your device, at least in the Android universe.
Therefore, a Xiaomi smartphone looks and operates differently than a Samsung smartphone when you pick it up. This is so that Xiaomi and Samsung could each create their own ROMs by altering the original Android code. Even though they both run Android, Xiaomi’s ROM and Samsung’s ROM are distinct from one another.
A custom ROM, then, is a ROM that was built not by the manufacturer but by someone else. Sometimes it’s just a lone programmer with some time on their hands and a passion for making ROMs—other times, it’s a bigger group like LineageOS that has a team and intentionally makes a certain type of ROM.
Once you’re rooted, you can flash a custom ROM. Flash, in this case, basically means to load or install. Flashing a custom ROM means you are installing a new ROM on your device and completely wiping the old ROM.
When looking for custom ROMs for your device, there are some names you’re likely to run into:
However, don’t be hesitant to try ROMs with different names from less well-known people. There are other reliable ones besides these. They’re simply the most well-known in general.
If you enjoy playing around with your Android device, the recovery process could take a while. It’s where you can perform the necessary heavy lifting, create backups, and flash ROMs.
You need a custom recovery because the stock recovery on your device is unable to perform any of those tasks. For installing custom ROMs, TWRP is the preferred custom recovery. Team Win Recovery Project is referred to as TWRP.
There are, of course, ways to backup your Android device without rooting it, but a Nandroid backup is a complete backup. It essentially makes a full copy of everything on your device and saves it. That way, if you screw up anything (since you have root access and that is possible), you can always just flash your Nandroid backup and return to where you were.
The name is just NAND (a type of flash memory) and Android mashed together.
The kernel is like the engine of your operating system—you don’t really see it, but it’s in the background doing all the hard work.
If you want, you can flash a custom kernel. Sometimes these kernels are optimized for performance or battery life—sometimes, they’re just necessary to get some feature to work right. Either way, you can be okay just sticking with your stock kernel unless you really want to change it.
Bricking your phone is essentially breaking it. If your phone isn’t working anymore, you’ve bricked it. This is generally not a phrase you’re going to be happy to run into.
If you end up bricking your Android phone, try these steps to try and unbrick it.
Google Pixel Watch 5 (45mm)
Robert Haba is the founder and editor-in-chief of Droid Tools. A lifelong gadget enthusiast with over a decade following the Android ecosystem, he built this publication to cut through the noise and give readers honest, real-world coverage of the tech they actually use.
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