There are various PC connection interfaces. In this category USB has the largest share of the market due to its ease of use and device compatibility.
-PCIe stands for PCI Express card bus and it is an internal bus.
-IEEE 1394,USB,eSATA are used for external hard disk connections
Most commonly used Video connectors include VGA, HDMI, and DVI.
-For connecting an LCD monitor, you need a digital signal connector such as DVI or HDMI. PGA, and VGA are analog standards.
-The different versions of USB cables, like USB 2.0 and USB 3.0, are concerned with the functionality and speed of the USB cable; whereas, the type of USB cable (like USB Type A, USB Type B) essentially refers to the physical design of the plugs and ports.
-USB is used for connecting USB-compliant peripheral devices, and eSATA is used for connecting external eSATA devices such as eSATA disk drives.