Death

Death is a common ailment in Crawl, and almost invariably lethal.

Unlike most RPGs, death in Crawl is permanent. Unless you are playing a felid with extra lives, when your character dies, your save file is deleted and the character is moved to the morgue, at which point a bones file is created for the floor and a player ghost may be generated in order to antagonize you in later games.

Reasons for death include:

Dropping below 1 HP due to monster attacks, traps, injuring yourself, or lingering effects like poison
Starvation
Drowning in deep water or lava (usually due to an expired Flight or similar spell)
Stat death by allowing your strength, dexterity, or intelligence to remain below 1 for too long

Here's an example of a quick death by monster damage...

The goblin hits you with an orcish club.
You die...

          18 Bob the Skirmisher (level 1, -2/15 HPs)
             Began as a Human Fighter on Sept 14, 2007.
             Slain by a goblin

...and here's one by falling down stairs.

In your confused state, you trip and fall down the stairs.
Ouch!  That really hurt!
You die...

             Len the Firebug (level 4, -9/20 HPs)
             Began as a Fire Elementalist on Oct 1, 2007.
             Died by falling of an stair