src/tech/index.md

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# Android Technical Information #
Welcome to the Android technical documentation section of the site. Here you
can find technical information useful to people and organizations who are
looking to modify, contribute to, or port the Android software. This is "under
the hood" information intended for engineers.

## Dalvik Technical Information ##
The Dalvik Virtual Machine is the heart of Android. It's a fast, just-in-time
compiled, optimized bytecode virtual machine. Android applications are
compiled to Dalvik bytecode and run on the Dalvik VM. This section includes
detailed information such as the Dalvik bytecode format specification,
design information on the VM itself, and so on.

[&raquo; Dalvik Information](/tech/dalvik/index.html)


## Bluetooth Technical Information ##
The Android Open-Source Project includes a bluetooth subsystem currently based
on the upstream bluez project. Android then layers various IPC and similar
libraries to link the bluez library with the Android Bluetooth stack and API.

[&raquo; Bluetooth Information](/tech/bluetooth/index.html)


## NFC Technical Information ##
The Android Open-Source Project also includes an NFC implementation. Unlike
the Android Bluetooth stack, much of the Android NFC stack is new code
originally contributed to the Android Open-Source Project. This code links the
Android NFC API to a device's NFC hardware. This section also includes
information on related Android technologies, such as the simple NDEF Push
Protocol.

[&raquo; NFC Information](/tech/nfc/index.html)

## Encryption Technical Information ##
The Android Open-Source Project includes the ability to encrypt the user's data.
This document is written for 3rd parties developing Android devices who want to
include support for encryption on their device.  It covers the few things that
must be done so encryption will work.

[&raquo; Encryption Information](/tech/encryption/index.html)