PCI is an abbreviation for Peripheral Component Interconnect. PCI is a type of bus which is used in connecting most personal computers to a network with some other personal computers. It allows a person, using a computer to share videos, files, music, pictures, and others from the computer with another computer.
While AGP is the abbreviation for Accelerated Graphics Port. The term implies, this component of the computer was built to meet the rising demands of 3-D video cards, which are extremely important, especially to people who play online games. AGP can be used to transfer videos and 3-D images, while PCI can be used for all these, and also used to transfer some other forms of data.
The express card of PCI is produced from some isolated components which are not joined directly into the slot, and having smaller space between the card bracket and connector, when in comparison to the AGP card.