When operating normally, air conditioners remove excess humidity from the air.
This moisture condenses, drips into a pan, and eventually drains. If your A/C is running full blast during the summer months, a few drops of water aren’t any cause for concern (especially for window units). However, if you have water dripping steadily from your air conditioner, or accumulating in a puddle on the floor, then you’ve got a problem.
Whether you call a professional or opt to make the repairs yourself, the first thing you need to do is shut off your A/C system. Running it while it’s leaking water will only make the problem worse, and will reduce the efficiency (and life) of your air conditioner.