Whale or Dolphin??
First thing's first: all dolphins are whales, but not all whales are dolphins.
That's because the Cetacean order of sea animals encompasses dolphins,
porpoises and what we think of as whales. And Cetacean is derived from the
Greek word for whale, ketos.
Whales and dolphins communicate with sounds, clicks and song
In return for helping the whales find the food they need to eat, the massive size
of the whales moving with the dolphins will usually deter any predators from trying
to attack or prey upon the dolphins. This is known as a symbiotic relationship,
which means that both parties in the relationship benefit from it.