GPIB programming

[L_K]

I have seen so many ways to program an application to transfer data thru GPIB, for example, there are VISA (eg. viClose, viOpen), NI-4882 API (eg. ibdev, ibclear), and CNi4882 (eg. write,read) class from Measurement Studio software. Can u tell me what's the difference between those and when do u use each of those? How they are related/categorized? Is there any caution when using those (eg. can mix or do not mix)? it would be nice too if u could give me some article to read about it. I want to get a big picture of those.
thank you

[JenK]

Irene,

Here are some documents that should answer your questions:

NI-VISA Help:
http://digital.ni.com/manuals.nsf/websearch/21992F3750B967ED86256F47007B00B3?OpenDocument&node=132100_US

Language Interfaces:
http://zone.ni.com/devzone/devzone.nsf/webcategories/0B47FD0CFA7E3F6E862567F4005AD89C

Please repost if you have further questions.

JenK