External connections of the computer
In system unit you need to plug things like monitors, and keyboards, and mices, and maybe a printer, maybe plug it into a network, you need to plug stuff in, you need to connect peripherals to this system unit, in order to take advantage of the power of this modern computer.
USB PORT
UBS's have been around now for 20 years, and it's pretty much taken over the universe if you're going to be plugging in a mouse, or a keyboard, or a printer, or something like that, it will probably use a USB.
Internet Connections
Network cable connections.
We use these types of connector called RJ45, for Ethernet or DSL.
Snap those into our systems so that we're on a wired network.
Sound ports
If you want to plug in a nice speaker system, you can use those round connectors.
The square connector is actually a fiber optic connection for more advanced audio systems where you can plug that in and you can have just one cable instead of five or six coming out of the back of the computer.
Digital Visual Interface (DVI)
DVI is an older type of connection.
DisplayPort
HDMI :Definition Multimedia Interface
it is very popular for audio and video interface to transmitting videos and audio data.
Power Connection
To extend electricity to the computer.
MINI-DIN PS/2 Connections
One for a keyboard and one for a mouse, it's kind of an old version of connections cable but it still using for some people who love to play games because they thinking that the PS/2 is more faster than USB for gaming.
Parallel port
It called also a (LPT PORT), it is used almost exclusively for printers.
Serial connector
Serial connectors provides a very slow speeds but there are some people usually use serial ports as an I/O interface in these days.
VIDEO GRAPHICS ARRAY (VGA)
This is a video connector. This is a very old-style video connector, and it was used to press monitors.