OBD II Brands

[1fastroadking]

Is there any difference in OBD reders between brands. In other words are any specific brands favored over others and who has the best price on the net.
I read about the Pelican brand and noticed it plugs into a port under the hood verses the plug under the dash. Whats the difference or will either plug tell you the same information.
What can someone tell me about "protocol". From what I read, although all
cars after 1996 are OBD II compliant some brands communicate in a different language. Is this something I need to know about when looking at readers.


Thanks

Richard