Layperson’s dictionary of rooting terms

So, you’re new to the Android community. First off, welcome to the wonderful world of customizing your phone! Android’s all about the power to make your phone truly yours and if you dig deep enough, you’ll find a hundred ways to make your phone unlike anyone else’s on the planet. Or, at least, nearly unlike anyone else’s. The more you customize, the slimmer the chance people will have the exact same settings. If you’re a stickler for individuality, you’ve made the right choice by getting an Android. But, the moment you loaded up Android Authority, you already feel overwhelmed by new words.

What’s a ROM? What does root mean? What are all these funny words people keep throwing at each other and what is the meaning of life? We’re kidding on the last one, sort of, but just like any newbie, getting into the world of Android is intimidating. You can still your racing heart and wipe those sweaty palms on your pants because Android Authority’s got your back covered. We’ve put together a list of some of the high-sounding words that newbies frequently encounter and compile the words into some sort of easy-to-digest layperson’s dictionary of rooting terms. Come across a word that you don’t understand? Check out our list, it should be here.


The acronym for Android Debug Mode. Whenever your Android device is connected to your computer, ADB is the command line tool that helps your computer communicate with your device. ADB is part of the Android Software Developers Kit (SDK) and is often used in root tools, whether or not you’re typing the commands in yourself. Unless the instructions call for installing the SDK and running ADB commands, you won’t need to mess with it.


Short for Android Open Source Project, you’re likely to see this in ROM descriptions. AOSP usually indicates that the ROM is based on the Android source code provided by Google itself, and not on some other ROM project or a company’s firmware.


Like it says on the tin, bloatware is software or apps that you don’t need, but come pre-installed to a device’s /system partition. What this also means is that you can’t remove them unless the device has been rooted. Usually, these are apps are sponsored by a company and are included by a carrier for profit. For example, the Photobucket app included on the G2 by T-Mobile is deemed by many to be bloatware, although, arguably, some folks do find the app useful.  Bloatware is a subjective thing.  Some person’s bloatware is another person’s lifeline.


A number of ROMs require your bootloader to be unlocked, but what in the world is it? The bootloader is the lowest level of software on your phone, running all the codes necessary to start up your operating system. Most bootloaders come locked, which prevents users from rooting their phones. This is because manufacturers want you to use the version of Android they’ve provided. With a locked bootloader on Android phones, you cannot flash custom ROMs. Unlocking your bootloader doesn’t mean rooting your phone, but it does allow you to root and to flash custom ROMs.

Boot loop

When your system re-cycles over and over without entering the main OS, your system is stuck in a boot loop and the phone is said to be boot looping. This may happen if you do not follow instructions.  At other times, boot loops are caused by defects in the software code. Usually developers who are aware of this problem include boot loop patches that must be flashed after you flash the custom ROM.


You’ve probably heard this one a few times. It’s usually the result of tampering with the insides of your device and doing irreversible damage. A brick can be the result of a faulty flash or firmware update, a mod gone wrong, or being struck by lightning. Brick refers to a device that no longer functions, generally caused by a failed firmware or SPL update. Since the device no longer works as intended, it is often referred to as a “brick” or “paper-weight”, since that is all it is good for. Since any modification to the device’s software could potentially brick it, following instructions is very important.


BusyBox is an application that provides a standard set of UNIX tools. The default toolbox provided by Android is limited, so BusyBox is required to allow rooted ROMs or apps to use more advanced UNIX features.

Dalvik cache

Sometimes in flashing ROMs, wiping the Dalvik Cache through Recovery Mode is important, but just what is the Dalvik Cache? The dalvik-cache directory holds all of the pre-compiled *.dex files created from installed apps. These files are static and do not change unless the app is updated.


This term is most often seen on a custom ROM’s list of features. When a ROM has been deodexed, it means that its apps have been prepared for modification. Deodexed ROMs have apps that have been repackaged in a certain way. Developers of custom ROMs choose to deodex their ROM packages, since it lets them modify various APKs, and it also makes theming possible after the ROMs have been installed.


Flashing is the term used to install something on your device, whether it’s a ROM, a kernel, or something else that comes in the form of a flashable ZIP file. It is the process of applying a firmware image or a ROM, to your device and usually entails a very specific order of steps. If you don’t follow instructions, you may end up bricking your device.


Fastboot is a boot menu that you can do stuff from before Android is launched. From this menu, you can choose to boot into Recovery Mode, and more. Fastboot is a protocol used to directly update the flash filesystem in Android devices from a host over USB. It allows flashing of unsigned partition images. It is disabled in almost all production devices since USB support is disabled in the bootloader.


A phone’s firmware is basically its operating system. A “firmware update” means that the operating system, the software that controls the phone, is updated. “Stock firmware” means that the firmware is unmodified: it’s the version of the operating system the phone’s manufacturer delivers.


When you switch your phone, HBoot is loaded immediately and is mainly responsible for checking and initializing the hardware and starting the phone’s software. HBoot can also be used for flashing official software releases, as well as a few other things.


The International Mobile Equipment Identity (IMEI) number is a number unique to every GSM, WCDMA, and iDEN mobile device, as well as some satellite devices. The IMEI number is used by the GSM network to identify valid devices and therefore can be used to stop a stolen device from accessing the network. For example, if a mobile device is stolen, the owner can call her or his network provider and instruct the provider to “ban” the device using its IMEI number. This renders the device useless, whether or not the device’s SIM is changed. The IMEI can be displayed by dialing *#06#. When a procedure asks you to take note of your IMEI, make sure to store it in a safe place.


The kernel is the heart of any Linux-based operating system. A kernel acts as the brain of the system and controls how the hardware and software interact. It also decides which activity your Android device should carry out at any particular instant.

NANDroid backup

Most how-to guides include this and all developers demand you to take a few seconds before flashing their ROM to make a NANDroid backup. NANDroid is a set of tools and scripts that will enable users who have root on access their Android device to make full system backups, in case something goes wrong or you would like to out an experimental ROM or theme. NANDroid will backup (and restore) the /system, /data, /cache, and /boot partitions. This backup can be restored later, whenever you want. NANDroid backups are created from the Recovery Mode, often with ClockworkMod Recovery.


This term refers to software whose source code anyone is allowed to view, modify, or redistribute. In the context of Android, opensource refers to the approach of the design, development, and distribution of software. This offers accessibility to a software’s source code for modification, improvement, bug-fixing, and security-enhancement. The CyanogenMod project is based on this principle.


This term is used when users want to increase the speed of their device’s CPU or GPU. Overclocking can be done by installing special kernels designed for this purpose.


The radio on your device handles communication and sending and receiving voice and data. Flashing new radio firmware can improve your radio hardware’s reception and bring other benefits. You can flash radio firmware through Recovery Mode, just like how you would a custom ROM.


Recovery is the software on your phone that allows you to make backups, flash ROMs, and perform other system-level tasks. The stock recoveries don’t do much, but if you can install a custom recovery such as the extremely popular ClockworkMod Recovery, you’ll have increased control over your device.  Other popular custom recoveries also include 4EXT Recovery and TWRP Recovery.


In the context of Android, a ROM (acronym for “read-only memory”) or, more specifically, a “custom ROM” is a modified version of Android. Developers may give it extra features, a different look, enhanced performance, and others. It may even be a version of Android that hasn’t even been officially released yet. Some of the popular custom ROMs you may have heard of are CyanogenMod, Android Open Kang Project (AOKP), and MIUI.

ROM Manager

ROM Manager is an immensely popular app for root users, allowing users to flash ClockworkMod Recovery, install ROMs from their SD card, perform backups, and even download new ROMs over-the-air.


Root refers to “administrator” or “full” access to the device.  That is, your device earns enhanced privileges and can grant you more control in customizing it.  The term referring to the process of gaining such administrative access is “rooting.”

With root access, you can mount the device’s internal memory partition as read/write, allowing you to do various things like USB or Wi-Fi tethering and uninstalling annoying bloatware. You can also enjoy certain applications that require root access, overclocking or underclocking the CPU, and more.

Some phones are easier to root than others. Certain phones require a tedious process to gain root access while other phones and firmware have easy and painless one-click methods. You can get root access by either installing the Superuser application or by flashing a custom ROM that already has root access included.  Check out our section dedicated solely for guides on how to root your Android device.

Rooting, unfortunately, also voids your warranty, so you must be extra careful with whatever you do to your phone after you’ve rooted it.


ROM Upgrade Utilities (RUU) and System Boot Files (SBF, for Motorola phones) are files direct from the manufacturer that change the software on your phone. RUU and SBF are how the manufacturers deliver over-the-air upgrades and modders often post leaked RUU and SBF files for flashing when updates haven’t been released yet. They can also be handy when you’re downgrading your phone, especially when a rooting method is not yet available for the newest software version. You can flash RUUs directly from your HTC device, but Motorola users will need a Windows program called RSD Lite to flash SBF files.


HTC phones use a security feature called Signature Verification in HBOOT, the bootloader on HTC devices. S-ON (security on) will read-lock your /system and /recovery partitions, blocking you from performing certain root-level actions directly from Android. By default, your phone has S-ON, which blocks you from flashing radio images. You can disable this security measure with S-OFF (security off), although you risk bricking your phone in the process but will allow you to flash new radios. Rooting doesn’t require S-OFF but many rooting tools give you S-OFF in addition to root access.


Since Android is a Linux-based operating system, Linux has something called root access. By rooting your Android phone, you gain superuser access. The superuser, or root user, is a special user account for system administration. Superuser is also the name of an app, which lets you grant or deny superuser privileges to other apps.


Usually refers to wiping data and cache partitions of the device. Usually before flashing a custom ROM, developers will instruct users to perform a wipe. Not performing a wipe may result in problems with the ROM’s performance.


You’re likely to see this term on the list of a custom ROM’s features. Zipalign is a tool that optimizes the way an Android app (APK) is packaged. The Android device can interact with an application more efficiently, and in doing so, has the potential to make the app and the entire Android system perform much faster. Zipaligned applications are launched more quickly, and they use less amounts of RAM.

Congratulations! You’re now equipped with some basic rooting and Android knowledge. Now you can dive into XDA Developers and feel less like a noob. Using your newly acquired knowledge, you can make better informed decisions when  looking for a ROM to power your Android device with. Good luck and happy hunting!

Got a rooting term that’s bugging you?  Let us know in the comments and we’ll try adding it to our dictionary.


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This article, Layperson’s dictionary of rooting terms , was originally published at – Your Android News Source.

By | 2012-05-14T05:00:10+00:00 May 14th, 2012|Android Related, Just the Tablets|0 Comments

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