Quotation marks, also called 'inverted commas', are of two types: single and double. British practice is normally to enclose quoted matter between single quotation marks, and to use double quotation marks for a quotation within a quotation:
The oceans absorb the sun's heat, transferring it to the atmosphere and distributing it around the world via the ever-moving ocean currents. This drives global weather patterns and acts as a heater in the winter and an air conditioner in the summer.
The importance of waves. To us surfers, ocean waves are much more important than they are for the rest of the population. In fact, they rule our lives. Without waves, the concept of being a surfer would be totally meaningless.