1.up to the present time;
I have yet to see the results
2.used in negative statement to describe a situation that has existed up to this point or up to the present time;
So far he hasn't called
3.to a greater degree or extent; used with comparisons;
looked sick and felt even worse
4.within an indefinite time or at an unspecified future time;
he will understand eventually
5.used after a superlative;
this is the best so far
6.despite anything to the contrary (usually following a concession);
although I'm a little afraid, however I'd like to try it