Page "Dungeons & Dragons" Paragraph 14

Hit points ( HP ) are a measure of a character's vitality and health and are determined by the class, level and constitution of each character.

They can be temporarily lost when a character sustains wounds in combat or otherwise comes to harm, and loss of HP is the most common way for a character to die in the game.

Death can also result from the loss of key ability scores or character levels.

When a PC dies, it is often possible for the dead character to be resurrected through magic, although some penalties may be imposed as a result.

If resurrection is not possible or not desired, the player may instead create a new PC to resume playing the game.