Typically, cats prefer to drink from water that has some movement to it, as opposed to water sitting flat in a dish. This is also the reason why many cats love to drink out of fountains, faucets and other sources of moving or aerated water.
In addition to preferring moving and aerated water as a source of hydration, cats are also drawn to reflective surfaces as a source of entertainment. Beyond play, and contrary to popular myths, many cats enjoy water. They seem to enjoy playing around with moving water in their dishes and cups to create ripples and see the effect.
Some breeds of cats with particularly long fur on their faces do not enjoy drinking water straight from a bowl or a dish, and prefer to dip their paws in the water first. This is also a common behavior if the level of water in the cat's dish changes from day to day. For example, if the dish contains a high water level in the morning, the cat may fear getting its face wet and chose to dip its paw in first. However, if the water level has dropped in the afternoon, the cat may be willing to drink straight from the bowl.