Why are there so many addresses, IQ, TCP/IQ, and Mac Address?

They are various ways of refering to basically the same information. However there are varying degrees of expressing it. A Mac Address is the IEEE registered ID for that network node, the TCP/IQ address is the address of that node within the network system, and the IQ address is a more basic description for that node within the network system. Another way to look at is as various ways of expressing where the Crown Factory is: The IQ Address would be "Crown Factory" - just a basic name that we can recognize The TCP/IQ Address would be "1718 West Mishawaka Road, Elkhart, Indiana, 46517" which is the address within the US Postal System. The Mac Address would be "Latitude 41.65600 degrees North and Longitude 85.99545 degrees West" which is a location definition that the entire world recognizes.