Question Author
\thank you all for your very comprehensive answers - I now understand it all!. The question arose because we are spending Christmas with the aged MIL who has no internet connection and I was wondering about taking the laptop and 'tethering' it to my phone. I have 1GB of internet usage per month allowed from my provider, included in my package. Would this be enough to spend a couple of hours a day, on the laptop, connected to the internet via my phone for a few days?