Anything inspirational lifts up your spirits. Inspirational words make people feel happier, more capable, and more like they can accomplish their goals.
Have you ever seen a proverb on someone's desk or refrigerator that they use to cheer themselves up? That's probably an inspirational quote. A lot of religious language is inspirational, and many actions can be inspirational as well. When someone climbs Mount Everest, that's inspirational because it inspires other people to do great or difficult things. When times are tough, people seek out things that are inspirational.