Wisdom measures your attunement to the world around you: your intuition, mental endurance, perceptiveness, and the other less-cerebral sides of intellect to intelligence.
Your Wisdom score applies in the following situations:
Wisdom is frequently used to notice details of the shared adventure world immediately around you, representing what you perceive in the moment—the present world obvious to your character as described by the DM. It is also used to understand feelings and emotions, read body language, offer appropriate care to others, and discern cryptic omens on an intuitive rather than logical level.
Some examples of Wisdom Tests include:
The Cleric, Druid, and Ranger classes use Wisdom as their Spellcasting Ability Modifier, which determines their Spell Attack Bonus (how easy it is to hit other people with spells) and Spell Save DC (how hard it is for creatures targeted by their spells to resist their effects).