GNet Solutions

• General Definitions
• Android Specific Definitions
• Hacking Definitions

General Definitions¶

• 3G
  3G is the term generally used to describe 3rd Generation mobile telecommunications, specifically allowing for greater throughput of data over cellular networks. The official standard is known as "International Mobile Telecommunications-2000 (IMT-2000)".

• Bloatware
  Software or 'apps' that you don't need, but come preinstalled to a device's /system partition, meaning that you cannot remove them unless the device has been rooted. Usually, these are apps are sponsored by a company and included by a carrier for profit. For example, the Photobucket app included on the G2 by TMobile.

• BFS
  Brain Fuck Scheduler for Linux was created by veteran kernel programmer Con Kolivas and has been reported to improve responsiveness on light-NUMA (non-uniform memory access) Linux mobile devices and desktop computers with fewer than 16 cores.

• CDMA
  Code division multiple access (CDMA) is a channel access method used by various radio communication technologies. It should not be confused with the mobile phone standards called cdmaOne and CDMA2000 (which are often referred to as simply CDMA), which use CDMA as an underlying channel access method.

• eMMC
  An embedded Multi-Media Card is a bit like a computer hard drive for smaller devices like phones and tablets. It's an embedded, internal storage medium that stores data such as programs, user information, images, music, etc.

• ext2
  Second extended filesystem for the Linux kernel. ext2 is still the filesystem of choice for flash-based storage media (such as SD cards, SSDs, and USB flash drives) since its lack of a journal minimizes the number of writes.

• ext3
  Third extended journaling filesystem is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions. Note that due to limitations of SD Cards, you need to run "e2fsck -f" on any ext3 based SD Card filesystems after a crash to ensure your data is still intact.

• ext4
  Fourth extended journaling filesystem is a journaling file system developed as the successor to ext3. Note that due to limitations of SD Cards, you need to run "e2fsck -f" on any ext4 based SD Card filesystems after a crash to ensure your data is still intact.

• Firmware
  Programs stored in the ROM, EPROM, or flash memory that usually control various internal electronic devices (Hard Drives, Keyboards, Displays, etc). Firmware is typically 'fixed' software that is not updated in consumer devices, however it is often updated (or 'flashed') by advanced users to fix bugs or add features to the device. Flashing firmware designed for one device onto a different device, or not following a specific procedure while flashing will often render the device unusable.

• Flash
  Non-volatile computer storage that can be electrically erased and reprogrammed (similar to EPROM). No power is needed to maintain the information stored in the chip. This technology is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products. Because of its ease of use, speed, ability to be updated (see flashing), this technology is often used in mobile devices, PDAs, digital media players.

• GNU
  A recursive acronym for “GNU's Not Unix!”; it is pronounced g-noo, as one syllable with no vowel sound between the g and the n. The GNU Project was launched in 1984 to develop a complete Unix-like operating system which is free software: the GNU system. “Free software” is a matter of liberty, not price. To understand the concept, you should think of “free” as in “free speech”, not as in “free beer”.

• GNU make
  A build utility (commonly called make); it interprets Makefiles, evaluates dependencies and issues build commands. See http://en.wikipedia.org/wiki/Make_(software). AOSP and Cyanogenmod use GNU make. Alternative build tools are cmake, qmake, autotools, ninja, and tup.

• IMEI
  The International Mobile Equipment Identity 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 their network provider and instruct them 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#.

• IRC
  Internet Relay Chat. Basically a chatroom, or a cross between Instant Messaging and a forum.
  Kernel
  The central or core software component of most operating systems. Its responsibilities include managing the system's resources (the communication between hardware and software components) and can provide the lowest-level abstraction layer for resources (especially memory, processors, and I/O devices).

• Open-source
  Open-source refers to software with publicly available source code. In the context of Android, Open-source refers to the approach to the design, development, and distribution of software. This offers accessibility to a software's source code for modification, improvement, bug-fixing, and security-enhancement. CyanogenMod is based on this principle.

• Radio
  The cellular radio on the device which needs control software called firmware to control it.

• ROM
  *R*ead *O*nly *M*emory. In the context of an Android device, ROM is the internal flash memory where the core operating system resides. It can also refer to a specific version firmware that can be applied to a device through a process usually referred to as flashing. An improperly flashed ROM can often brick the device, rendering it unusable.

• SuperCID
  SuperCID is a special code, 11111111, which means that software from any region can be installed. See superCID

• SDK
  Software Development Kit. You can find the Android SDK at http://developer.android.com/sdk

• Vanilla
  A clean, unmodified version of something. In the context of Android ROMs, vanilla refers to the stock ROM that came pre-installed on the device.

• Widget
  An application that lives (in other words, is always running) on the homescreen instead of being 'run' like a regular app. Common examples are calenders and weather widgets.

Android Specific Definitions¶

• 32A
  PVT32A handsets have 288MB total RAM (192MB usable by OS - same as Hero handsets) and use the Qualcomm MSM7200A CPU.

• 32B
  PVT32B handsets have 192MB total RAM (96MB usable by OS) and use the Qualcomm MSM7201A CPU.

• ADB
  Android Development Bridge Command line tool used to communicate with & control the device over a USB link from a computer. The ADB command is found in the Android SDK.

• ADP
  Android Developer Phone. The first ADP was a "development" version of the HTC Dream.
  Beginning with HTC's Nexus One (codename "passion"), all ADP devices received the brand name "Nexus".
  Additional ADP's are Samsung Nexus S, Samsung Galaxy Nexus, Asus Nexus 7 (tablet), Samsung Nexus 10 (tablet) and LG Nexus 4.
  The current ADP is the LG Nexus 5, announced 31 October 2013.

• Android
  Unveiled on 5 November 2007, Android is a mobile operating system developed by Google running on the Linux kernel.

• Apps2SD
  Move applications from the internal NAND memory on the device to a removable SD Card. Alternatives include Mounts2SD and Link2SD

• CM
  Short for Cyanogenmod

• CWM
  Short for ClockworkMod Recovery. Not to be confused with CM (Cyanogenmod).

• 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.

• Fastboot
  Fastboot is 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 almost all production devices since USB support is disabled in the bootloader.

• flash_image
  A small utility to be used on the device that allows you to re-write system partitions with image files. If you don't have it, it can be found here

• GApps (Google Apps)
  An add-on for Google's applications (Market, GMail etc.), packaged separately to avoid copyright issues

• Hboot
  Hboot is a common manufacturer term from HTC for the bootloader.

• Logcat
  A debugging tool built into Android devices that displays system logs as they occur. See Logcat

• NANDroid
  A set of tools that will enable anyone who has root on their Android device to make FULL system backups, in case something goes wrong or you want to try out that new experimental ROM/theme. NANDroid will backup (and restore) /system, /data, /cache, and /boot partitions.

• NVFlash
  is a low-level flash utility for nVidia based devices which gives you low level access to the system to flash, format, recover, repartition and do many more functions. It is a very powerful tool and should be used with caution. Read and follow all instruction carefully when using nvflash. See http://rootzwiki.com/topic/35086-guide-nvflash-general-users-guide-unbrickrecoverdowngradeupgrade-tf201/#entry982736

• Recovery Mode
  A special environment that you can boot into for troubleshooting and upgrading purposes.

• SPL
  Second Program Loader, in conjunction with the IPL comprise a device's bootloader. Aside from bootstrapping Android, the bootloader also fulfills various diagnostic functions. One of these functions is the manipulation of data in the device's internal flash ram. Depending on the SPL installed, the user might be able to flash signed NBH files, flash nand images, and more. Note that the SPL is installed and operates independently of the Android build that runs atop it.
  Generally speaking, there are two variants of the SPL: Stock, which is 'locked' and is installed on most devices from the factory, and Engineering, which is 'unlocked' and has to be manually flashed - usually after 'rooting'.

• S-OFF
  Usually a property of HTC devices. S-OFF allows the user to modify any partition on the device. Signature checking is disabled for zips, allowing the user to flash otapackages and custom kernels from recovery. S-ON prevents the user to allow these actions. Note that S-OFF does not imply that a device is rooted. See http://forum.xda-developers.com/showthread.php?p=26732440 for more information.

• Tethering
  Using a device (e.g. an Android phone) to share its 3G/LTE data connection to another device (e.g. laptop). With an Android device, the data connection can usually be shared via WiFi, Bluetooth or USB.

• Wipe
  Usually refers to wiping data and cache partitions of the device.

• Zipalign
  Reduces the amount of RAM consumed when running the application by allowing data to be mmap'd in; which causes all uncompressed data within the .apk, such as images or raw files, to be aligned on 4-byte boundaries.

Hacking Definitions¶

• Aftermarket
  Aftermarket generally refers to any product or service applied or requisitioned by end-users to add usability or functionality to the original product. Many aftermarket modifications can void the manufacturer's warranty. From a manufacturer's perspective, the after-market is any goods or services offered by the manufacturer directly to end-users of a given product or service. After-market services include support for warranties, contracts, and parts and accessories sales.

• Brick
  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.

• Exploit
  A proof of concept local root exploit utilizing hotplug. Allows installation of a "rootshell" program on many Android 1.x and 2.x devices.

• Flashing
  The process of applying a firmware image (or ROM) to a device. It generally entails a very specific order of steps. Failing to complete any one of these steps properly may result in bricking the device.

• Kang
  The process of creating a code based off someone else's code or reapplying code that someone else created into your own code (e.g. git cherry-pick). The term "kang" or "kanging" can have a pejorative connotation, especially if one adopts code from someone else without giving due credit. However the term can also be used with a certain sense of irony; sometimes one will claim to have "kanged" with some tongue-in-cheek.

• Rooting
  Obtaining root ("administrator", or "full") access to the device. This means you can mount its internal memory partition as read/write, which lets you do various things: have USB or Wi-Fi tethering, uninstall applications you otherwise can't uninstall (e.g. the Amazon MP3 store), install applications that need root access (such as AdFree ), disable the camera shutter sound (simply by deleting the shutter sound file), overclock or underclock the CPU, install and boot Debian, and so on. Installing CyanogenMod roots the device in the process. The "Superuser" app controls what applications may gain root privileges.

• Unlock
  Most GSM devices are locked to only work with the sim cards of a particular carrier. Obtaining root access (e.g. installing CyanogenMod) on the device usually does nothing to the sim-lock. The usual way to unlock the device to all SIM cards is to obtain a subsidy unlock code from a carrier.