Sizes and Versions

• Currently, there are standard-, mini- and micro-sized versions of USB ports and plug-in devices. In addition to carrying data from one device to another, USB ports are also capable of transferring power, enabling the connected device to charge while the connection is intact. Presently, USB version 2.0 is the most common type of USB technology used on computing devices. USB 2.0 provides transfer speeds that are reported to be 40 times faster than those achieved by USB version 1.1. Contrary to what the name implies, "full speed" USB 1.1 connections are actually slow speed, while USB 2.0 "high speed" connections are just what its name implies.
  
  

Software and Mass Storage

• Some computers require particular software applications to be installed before data can be transferred from a mobile phone to a computer. Most phones on the market in 2011 feature a "mass storage" mode that does not require intermediary software, but only allows for transferring files. When using this mode, most mobile phones require you to change the phone's settings to this mode. When connected using this mode, the device appears as a disk on the computer's screen, much like a flash drive or external hard drive. Transferring files from this point is done by dragging and dropping files from one device to the other.
  
  

Interfacing

• Some mobile phones support USB-Host, also known as USB-OTG, which give you the option of connecting the phone directly to a USB accessory, such as a printer. Some mobile phones support PictBridge, an application that allows you to connect a digital camera or camera phone directly to a printer. To take advantage of this feature, the printer must also be capable of supporting PictBridge.
  
  

Miscellaneous

• A single USB port is capable of supporting up to 127 peripheral devices, including mice, keyboards and modems. In 1996, computer manufacturers began installing USB ports on their newer computers, but it wasn't until Apple added USB technology to its popular iMac in 1998 that the technology became widespread. Super-speed USB, also known as USB 3.0, is the newest USB to hit the market and began appearing in computing devices in 2010. USB 3.0 technology provides transfer rates at up to 5 gigabits per second.