What is a USB Hub?
A USB Hub is a device that can be used to create multiple USB ports, allowing for more USB peripherals to be used. A standard computer has two USB ports built-in. But in today's market, where just about everything, such as printers, scanners, and even mice, requires a USB port, a person will need more than just two USB ports.




What is a USB?
USB stands for Universal Serial Bus.
There are several different versions of USBs.
USB 1.0

• Original USB
• Defined 2 speeds for USB peripherals: Low-Speed (LS) at 1.5Mbps and Full-Speed (FS) at 12Mbps.

USB 1.1

• Maximum transfer rate of 12Mbps

USB 2.0

• Standard USB version used today
  
• Raw data transfer rate at 480Mbps
  

USB OTG

• Stands for Universal Serial Bus On-The-Go
• For hand-held, portable devices to share data without the use of a computer

How does a USB Hub work?
A USB Hub will connect a USB port. The USB Hub contains mulitple USB ports on it, that other USB peripherals can be connected to. All the devices connect to the computer through the USB Hub will receive power, as if it were directly connected to the computer (unless it requires its own power).










What are the different types of USB Hubs?
USB Hubs can be powered or unpowered, depending on the preference of the user. A powered hub has its own transformer and supplies its own power to the bus so the device does not required power supplied from the computer. If the USB peripherals do not require power from the computer, such as printers which plug into a regular power outlet, an unpowered hub can be used.






Sources:
Information:
http://computer.howstuffworks.com/usb2.htm
http://www.wisegeek.com/what-is-a-usb-hub.htm
http://www.planetanalog.com/features/showArticle.jhtml?articleID=197006216
http://www.everythingusb.com/usb2/faq.htm

Images:
http://upload.wikimedia.org/wikipedia/commons/thumb/4/46/USB_hub.jpg/250px-USB_hub.jpg
http://computer.howstuffworks.com/usb2.htm
http://www.everythingusb.com/templates/images/logos/hispeedusb.jpg
http://i.cmpnet.com/planetanalog/2007/02/C0161-Figure7.1.gif