Recuperation

Each D&D character has a handful of Hit Dice (so called because they're the dice that character originally rolled (or took the average thereof) to determine their Hit Points). Over the course of a Short Rest, a character can "spend" any number of hit dice, roll them, add their Constitution Modifier to each die result, add it all up, and regain that many Hit Points. The D&D rules don't seem to have a name for this ability, so I call it Recuperation. (Oh, and if you were wondering, characters can regain a number of "spent" Hit Dice equal to half their character level, rounded down, to a minimum of one, at the end of each Long Rest.) Recuperation is hardly an essential ability in D&D, since most classes have some access to healing spells or abilities, and characters regain all their HP at the end of each Long Rest anyway. D&D characters don't often need to recuperate. But we do.

We get tired. We get cranky. We occasionally feel incapable of being the best possible versions of ourselves. At such times, it may be wise to take a rest. It doesn't have to be a long rest, and it often can't be, but if we can pull ourselves aside for a moment and take a breather, we can sometimes regain a sufficient amount of physical and emotional energy in a relatively short of time.

When we feel low on energy (physical, emotional, spiritual, or any other kind), it may be wise to try and get some of our energy back by taking a short rest to recuperate it.