1747-Pic Compared To the 1747-UIC

Can Anybody Please Tell Me what The Differance Is? I Am Just Getting Started On PLC Programming. I Have Purchased The PLC Tutor Book From The Site.
I Was Given A 5/02 Processor And A Few Input And Output Cards Just To Play With.
However I Can Not communicate With The Processor. I Was Told Because My Lap Top Has the USB And Not the Serial Port I Would Need the USB To Serial Port Adaptor And The 1747-PIC. After Purchaeing this I Still Can Not Communicate. I Have Purchased The SLC 500 With RSlinx Standard Software.I Was Reading A Post On Here About the 1747-UIC Being Used With The New USB Port. I Know I Can Communicate On Com1 With My USB Adaptor Due To Programming IDEC PLC
NEWBBIE Take It Easy On Me
thanks In Advance

Have you read this:
http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1747-in063_-en-p.pdf

The 1747-PIC ia a RS232 to DH485 converter
The 1747-UIC ia a USB to DH485 converter.
If you don't have a real serial port the 1747-PIC is useless.

To add a little more information:

The 1747-PIC ia a RS232 to RS485 converter. It electrically converts the information coming from a serial port. The information will be using the DH485 protocol.

The 1747-UIC recieves DF1 protocol via the USB. It converts the protocol to DH485. It then provides this converted protocol in two electrical formats - RS232 and RS485.

Does such a device exist that will go from USB to DH+?

Maybe, check here:
http://www.protocolconverter.com/products/DL3500.htm

http://www.equustek.com/