Iphone 4 won't sync calendar events with iMac's ical

I got an iphone specifically because I assumed it would work effortlessly and flawlessly with my imac. I was wrong.

I had to get a third person to sync contacts with the iphone, but now cannot understand why an event that was entered

to the iphone's cal won't transfer to ical on my imac.

I hope someone can offer some help. Thanks in advance.

btw everything worked well with my android phone.