wired connections


USB stands for universal serial bus. There are 4 different pairs of USB-

standard type A

standard type B



standard type A is what you use in peripherals like keyboards and mice.

standard type B is what you plug in pheripherals like printers and scanners

mini wasysed for smaller devices like mobile phones and digital cameras that cannot fit a bigger standard usb on the device

micro is newer than mini and it is even smaller than mini and it is the new standard for smart phones and tablets, digital cameras so it eliminates the needs for mini.

There have also been three main versions of USB-

USB 1.0

USB 2.0

USB 3.0

USB 1.0 is no longer in use and got replaced by USB 2.0

The speeds range from low bandwidth which is 1.5 mbits/s to12 mbits/s by today standards are slow.

USB 3.0 -The USB 3.0 specification is similar to USB 2.0 but with many improvements and an alternate implementation. Earlier USB concepts like endpoints and four transfer types (bulk, control, isochronous and interrupt) are preserved but the protocol and electrical interface are different.


HDMI which stand for High Definition Multimedia Interface, there are five types of HDMI cable connectors.

Type 1: Type 1 contains 19 pins with bandwidth to support all the modes which are SDTV, EDTV and HDTV modes

Type 2: Type 2 contains 29 pins and carries six different pairs instead of three for use with high resolution future displays such as WQUXGA(Wide Quad Ultra Extended Graphics Array). Type B is electrically compatible with dual link DVI-D

Type 3: Type 3 is a mini connector defined in the HDMI 1.3 specification, it is intended for portable devices. and contains 19 pins

Type 4: a micro connector defined in the HDMI 1.4 specification and keeps the standard 19 pins of types 1 and 3 but shrinks the connector size to something resembling a micro-USB connector

Type 5: an automotive connection system defined in HDMI 1.4 specification. The connector has a locking tab to keep the cable from vibrating loose and a shell to help prevent moisture and dirt.


Firewire is a method of transferring information between digital devices especially audio and video equiptment. Fire wire is fast and the latest version achieves speeds upto 800 mbps and the future that number is expected to jump to 3.2 gbs.


Thunderbolt allows users to connect to monitors sport mini displayport or displayport connections. Adapters can allow for HDMI, DVI and VGA connections as well but it doesn't stop with these less ambitious technologies. Thunderbolt provides support for optical connections to connect to high speed networks.


One by one. Serial data transfer refers to transmitting data one bit at a time. The opposite of serial is parallel, in which several bits are transmitted concurrently.