Totally normal, Terrible 2s are a misunderstood thing before you have your own kids, you think it is only the year after they turn two - it is really more like from 1-4, in varying degrees! Both myy kids started tantrums around 1, got to its worst around 2, and is still an occassional thing with my 3 and a half year old, and very prevalent with my 19 months old! It is normal, they are learning they are independant and that that CAN actually make choices and control some things in their lives, and are trying desperately to do so!
Try to pre-empt them by keeping the routine of the day, order of things done, try to ease transitions with a timer - "when the time goes beep we will start to clean up the toys so we can have lunch" etc. Make sure the child is not overly tired, hungry, or tirsty - many times those things can trigger tantrums, and the child can't tell you yet what he needs - so offer a drink, a snack,or a nap!
Good Luck! Sometimes they just need a time out - not punishment style, just some quiet time in their crib in their room, or in a quiet area in a play pen...kids get overwhelmed too!
Jessie