I don't know where else to post this, so here it goes.

I am interested in adding bar code wand/scanner functionality to an app. The reader was already givne to me (UniTech MS210U), and it supports these types of bar codes:

UPC-A
UPC-E
EAN-13
EAN-8
I 2 of 5
S 2 of 5
Code 39
Codabar
Code 93
Code 128
UCC/EAN128
MSI
Code 32
Plessey Code
Label Code IV,V
China Postal Code

I have only heard of "Code 39", that's the extent of my knowledge. Can anyone say why a given code would be used over another? The kind of data I want to bar code will be an int, a long, or a GUID.

Thanks.