Why is my car making a loud BOOM noise when putting it in Drive from Park?

Why is my car making a loud BOOM noise when putting it in Drive from Park? - 1

Added (1). I have a 1998 Honda Accord. From one day to the next i got in my car in the morning to go to work, turned it on, put the car in D4 from park, let go of the brake, and heard a loud "BOOM". Can someone please tell me why this is? When i drive, it takes a little long to get out of first gear and when it does change gears, my RPMS sky rocket to around 5 or 6 and i get a BOOM. I have limited knowledge on cars, you are talking to a dummy.

Get this to a transmission shop As soon as possible before you do any more damage

Check fluid level and condition. Smell it, and if it smells like burnt dinosaur terds get to a trans shop.

http://autorepair.about.com/