What is the difference betwen a "messenger" and a "courier"

African or european swallow?

I've heard the reason why cabbies are such wankers to couriers is that people often used to pay the fare up front and have them deliver 'important' packages and documents. then the couriers took all that work away.

Probably bollocks though. Wigan might know, since he's 72 years old.

There was a period, after account fares came in and before widespread courier companies, in which taxis were used. It was cheaper to give the package or letter to a cabbie rather than send a messenger there and back by cab. Couriers worked out much cheaper and so the use of cabs for deliveries disappeared.

Not sure, however, if that is what made cabbies wankers. That could be in the DNA.