- we want a predictive science
- we measure running time as a function of n. The size in bytes of the imput
- we work on the RAM model of computation
- All reasonable operations take "1" unit of time(for example one byte of I/O
what is the runnning time of an algorithm?
- Best case (sheldom used)
- average case (used if we undertand the average)
- worst case (used most often)