From XDA-Developers

This article is about the Verizon Galaxy S III. For other models, see Samsung Galaxy S III.

Specification

Manufacturer:	Samsung
Release Date:	06/2012
Operating System:	Android
Dimensions:	136.6 x 70.7 x 8.6 Millimeters
Weight:	133 g (4.7 oz)
Chipset:	Qualcomm Snapdragon S4 MSM8960
Display:	4.8 in (120 mm), 1280×720 pixels, 306 ppi (pixel per inch), HD SUPER AMOLED RGBG-Matrix (Pentile)
Networks:	2G GSM/GPRS/EDGE 850, 900, 1800, 1900 MHz 3G UMTS/HSPA+ (21 Mbps down, 5.76 Mbps up) 850, 1900, 2100 MHz 4G LTE 700, 1700 (AWS) MHz
Wifi:	802.11 a/b/g/n, Wi-Fi Direct, Wi-Fi hotspot
Bluetooth:	4.0
NFC:	Yes
GPS:	Yes
Video out:	Not Known
Camera:	8.0 megapixels with LED Flash
Secondary Camera:	1.9 megapixels
Internal Memory:	2 GB RAM / 16/32 GB (11.2GB/28.2GB available)
Memory Card:	MicroSD upto 64GB
Battery:	2100 mAh
Additional Features:	TouchWiz "Nature UX" UI

Introduction

XDA-Developers Forums for the Phone

How to get into Recovery Mode

Unplug the USB cable.
Shut down the phone.
Hold down the 'HOME' + 'VOLUME UP' buttons and press the 'POWER' button for about 5 seconds to enter Recovery Mode.

How to get into Download Mode (eg: for Odin)

Unplug the USB cable.
Shut down the phone.
Hold down the 'HOME' + 'VOLUME DOWN' buttons and press the 'POWER' button for about 2 seconds until a WARNING! Screen appears. Press the 'VOLUME UP' button to enter Download Mode.
To get out of Download Mode, simply press and hold the power button until the phone restarts.