A clear definition of the differnt stake amounts

[filmsimon]

Hi,

I was wondering if there was a clear cut amount for the differnt stake amounts.
i currently play 0.05/0.10 limit holdem online and I understand this is classed as micro stakes. when does this become small stakes and then medium and high stakes?

I understand there's differnt styles of play at each level so I was wondering when someone should look to change there game slightly when moving stakes.

Thanks

Simon burgin