If you go swimming in the ocean, please remember:
In the event of being caught in a rip tide DO NOT FIGHT IT and attempt to swim directly back in to the beach; you will only get tired and then drown. Swim parallel w/ the beach and you will eventually get out of it and able to get back.
Watch for changes in the water color and if that corresponds to areas where the waves aren't breaking (or breaking as much), that's likely a rip tide.