Comparing AC and DC is the usual type of question:
AC -
GOOD
- Easily and efficiently transformed due to alternating nature
- efficient power transmission due to transformation
- AC generators are easier to maintain and more reliable due to fewer parts
- easy to utilise in household applications
- Slip rings means less wear than commutator in DC
- Three phase induction makes easy generation of electricity
BAD
- the hum that AC produces due to oscillating nature interferes with electronics
- constant back-emf
DC
GOOD
- No back emf once current is flowing
- provides steady voltage and currrent output for some specific tasks
- heavier loads
BAD
- heavier loads also means increased risk of damage due to heavier rotor
- the commutator spins alot so friction can wear it out and needs repairs or reduces efficiency
- hard to transform.
As one can see, DC sucks ass.