3G Stands for 3rd-generation. Analog cellular phones were the first generation. Digital phones marked the second generation (2G).
3G is loosely defined, but generally includes high data speeds, always-on data access, and greater voice capacity.
The high data speeds are possibly the most prominent feature, and certainly the most hyped. They enable such advanced features as live, streaming video.
There are several different 3G technology standards. The most prevalent worldwide is UMTS, which is based on WCDMA. (The terms WCDMA and UMTS are often used interchangeably.) UMTS is the 3G technology of choice for most carriers that used GSM as their 2G technology.
Bluetooth is a short-range wireless technology used to create PANs (Personal Area Networks) among your devices, and with other nearby devices.
Bluetooth allows you to leave your phone in your pocket, while talking on your phone with a Bluetooth headset - with no wires. You can also exchange contact or scheduling information with other Bluetooth-enabled phones nearby, or send such information to a nearby Bluetooth-enabled printer.
Another common use is to give your laptop computer or PDA wireless high-speed Internet access via Bluetooth and your phone.
Many newer automobiles also have Bluetooth, which can interface with a phone in a pocket, to allow automatic hands-free phone capability.
More innovative uses include playing a game against someone with a similar phone nearby, or using a special Bluetooth pen to send SMS messages by simply writing them on paper.
Bluetooth functionality is divided into separate types of connections known as "profiles". Each of the various scenarios outlined above involve a different profile. Not all Bluetooth devices support all profiles.
For example, most phones support the Headset (HSP) and Handsfree (HFP) profiles, for connecting the phones to headsets and car kits, respectively. But not all phones support the Object Exchange (OBEX) profiles, which let you transfer files (like photos) (FTP) and/or information (like contacts and events) (OPP) to and from other devices. Another profile supported by only some phones is Dial-Up Networking (DUN), which lets you connect a laptop or PDA to the Internet via the phone. Other optional profiles support connecting to printers (BPP), keyboards (HID), and stereo headphones (A2DP, AVRC).
Most Bluetooth phones are "class 2", which means the Bluetooth feature has a range of up to 30 feet. Class 1 phones (which are rare) can have a range of up to 300 feet.
Bluetooth is named for the 10th century Viking king Harald Bluetooth, who united Norway and Denmark.
Multimedia Messaging Service
MMS is a descendant of SMS (Short Messaging Service). MMS extends text messaging to include longer text, graphics, photos, audio clips, video clips, or any combination of the above, within certain size limits.
MMS is frequently used to send photos and videos from camera phones to other MMS phones or email accounts. Most camera phones have MMS, but many non-camera phones have it as well.
Many newer MMS phones also support SMIL, which allows various parts of an MMS message to be arranged into a small multimedia "slideshow" to be viewed on another SMIL-capable MMS phone.