What are Spring and Neap tides?

Mona had gone to visit her friend's boat on the Visakhapatnam jetty. She was surprised to see that the boats seemed to have sunk because the water level in the jetty was low and the gangways to the boats were almost vertical. As a student of geography name and explain the phenomena that caused this.

For what is the Gulf Stream famous?

What happens when warm and cold currents meet?