What is root?
'Root', is the name of the login account in the Linux operating system that has complete full access to all system resources. It is also referred to as 'superuser'. This is akin to the 'Administrator' account in Windows. Essentially it gives you full access to any file in the operating system. Android is a modified version of Linux built for mobile devices. Hence forth the same terminology for Linux applies for Android.
As with computers, it is often beneficial to lock down accounts to prevent end-users (you and I) from altering data that can potentially break the functionality of the system by limiting access to certain files and actions. However, by locking down the end-user, it also means that the user loses full control of the system. Typically access is denied to this account on retail mobile devices.
'Rooting' refers to the process by which the user gains access to the root account.
Being 'rooted' is when the end-user has the ability to login to the root account. When rooted, the shell (terminal, or command prompt) will either display a '#' sign to the left, or has the ability to do so. To the right you will see a root shell on an Android device in the application 'Terminal Emulator'.
The benefits for a manufacturer to lock down the device for end-user use is obvious: avoid unnecessary technical support, and limit functionality not required by the typical end-user.
What are some of the things I can do if I have root to my Android device?
- Custom firmwares bringing increased performance and functionality
- Custom themes
- Changing core (system) applications such as calendar, maps, clock
- Freedom to do as your wish on your own phone
Here's a sample of functionality otherwise not available on some unrooted devices enabled after rooting:
- ability to take a screenshot on the device without use of additional tools
- control the CPU, including undervolting and overclocking
- control the keyboard backlight
- perform backups and restores quickly and reliably using superuser-only tools
- access to the international Android market
- data access control via application whitelists or blacklists
- install applications on the SD card
Small gallery of functionality enabled by being rooted:
SetCPU (stock Rogers HTC Dream clocks at 384 MHz)
Wait isn't this dangerous?
Root access allows the end-user to perform otherwise restricted actions such as modifying system files.
Is this dangerous? Potentially? Yes.
Are the chances of me screwing up my phone or mobile device high? Depends on what you are modifying, but in most cases, no.
As long as you are careful to read to understand the consequences of what you are doing to your phone, you will not end up with an expensive brick!
If you do not understand what you are doing, read first and ask if you still do not understand! This is important!
- "root - Linux Terms". Linux Self-Help. http://www.linuxselfhelp.com/linuxterms/index/root.html
- "Why Root - Android Wiki" Android-DLs http://android-dls.com/wiki/index.php?title=Why_Root