A captain has to navigate through shallow waters. She does so using math.
The CyberSquad is on an island and needs to visit Dr. Marbles. The group members have a map but don't know where they are on the island, so they head to the shore. Once at the shore, they use landmarks to determine where they are on the map. From there, they figure out which direction and how far to travel in order to reach the doctor.
Inez and Digit need to get Peaches home to her family, and they use a map to help them navigate the island to the peach trees. At first, they head in the wrong direction. However, they use landmarks to find their position on the island and determine the direction they need to go in order to reach their destination.
This clip explains that Edmond Halley created a map of the stars, which made it easier for people to navigate from place to place. Neil deGrasse Tyson talks about how people were lost prior to astronomy when they went sailing in the seas.
Destiny introduces Dory to her neighbor, Bailey, a beluga whale who claims to have lost his ability to find objects using sound waves. Bailey believes that his head is swollen, but Destiny states that his head is naturally that big because of his species.