Capillarity is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity. This phenomenon is crucial for the functioning of kerosene lamps, where fuel rises to the wick. Similarly, blotting paper absorbs ink due to capillary action. The ascent of water from the roots to the leaves in tall trees is also a consequence of capillarity, along with transpiration pull and adhesion/cohesion forces. However, drinking with a straw relies more on atmospheric pressure pushing the liquid up into the straw as you reduce the pressure inside it.