can if then else be used in a formula

hi
can you use if then else in a formula like
if a1 07:00hrs is less than f1 08:00hrs then difference is1
what im trying to do is our working day is 08:00 to 16:30, 0700=0800 is o/t1.5 but 00:00 to 07:00 is o/t2,else 08:00 to 16:30 is single ,so if I go to work at 06:00 I would have 1 at x2 and 1 atx1.5, and 8 hrs at normal time,how could this look in a formula have tried a few today but getting tied up in knots
cheers colin