differential

I was on the lookout to buy a calling card which is the cheapest way to call a UK Mobile since Skype and Yahoo! Voice Out rates were more expensive than calling from my Airtel mobile. Almost all operators, Tata Indicom, Airtel, etc. which sell International Calling cards have differential rates...

When accessing internet do we get some speed differential means do internet surfing is faster when done on Linux or windows offers high Speeds??