Health

The health gauge and monitor in Minecraft is based on a single row of 10 heart icons. Each full heart contains two halves, one hit point each (full health is 20 hit points).

Damage from attacks or natural causes will subtract hearts from this total. When the total reaches zero you die. When a mob dies, it drops items specific to that mob, Players drop their inventory when they die, and when Notch dies he drops a red apple in addition to his items.

Armor will absorb damage and reduce the number of hit points subtracted from the player's (or mob's) health (damaging the armor instead).

Creative Mode
In creative mode the player still has health, but it is hidden from the interface, and the player is invulnerable to everything except falling into the void.

Hearts
Hearts make up the health meter for the player and mobs in the Survival modes. Each heart represents two hit points, for a total of 20 hit points. Hit points are lost in multiples of one point (i.e. half heart).

Hit points can be lost by: starving; taking fall damage; being attacked by a hostile Mob (or another player if PvP is on); being shot with an arrow; being on fire; touching lava, fire, or a cactus; drowning underwater; suffocating inside a block; falling into the void; being affected by negative potions, or getting caught in an explosion. When the health meter shows two or less hearts (20% or less health), it will begin to shake violently, warning that the player's demise is imminent if health is not restored.

On Peaceful difficulty, the health meter will refill over time. As of 1.8, health is not restored by consuming food, but rather slowly regenerates when the player's Food Bar is at or above, and regenerates fairly quickly for 4 seconds after eating a Golden Apple or 45 seconds with a potion of regeneration.

Damage is split between the health and Armor bars. Each full armor point takes 8% of damage, to a maximum of 80%, rounded up.

On Hardcore mode, hearts have a different texture

Also,hearts can be generated with a food level of 9 or more if not on Peaceful

Dealing damage
Players can deal damage by hitting mobs or other players with items at close (melee) range. A large majority of items only deal damage. Weapons can be crafted for the express purpose of dealing more damage. Swords are crafted for this purpose. While swords do not extend attack range, they deal significantly more damage than with any other item or tool. Axes, pickaxes, and shovels also deal more damage than bare fists however, with hoes doing the same damage as fists, as detailed on the Weapons page. While falling, melee attacks deal a critical hit (150% damage + damage, rounded down to the nearest hit point).

Arrows (shot by holding and releasing right click when wielding a Bow), snowballs, splash Potions, and chicken eggs are the only ranged weapons in the game. Snowballs only inflict damage on Blazes and the Ender Dragon, while eggs do no damage at all, but still knock mobs back as if they had been damaged. Splash potions can be thrown, inflicting various effects depending on the potion.

The Flint and steel allows the player to light a block on fire, which causes all players and mobs that touch the fire to be set alight. Players and mobs that are ignited stay alight until hit points of damage is dealt or until they touch water. Likewise, contact with Lava also ignites players and mobs.

TNT is currently the only explosive (other than creepers) in Minecraft and is obtained by crafting sand and gunpowder.

The below values detail the damage dealt per hit using various items. Note that weapons and tools in 1.8 dealt more damage, and that critical damage is not consistent.

Damage inflicted by Mobs
Unlike player character's damage, the damage most Mobs deal is affected by the difficulty of the game. The below values represent the amount of damage taken per hit.
 * Values for the Creeper and Ghast assume the player is directly adjacent to the explosion.
 * The damage of Slimes and Magma Cubes depends on their size. Tiny-sized Slimes, while hostile, are unable to do damage directly.

Knockback
When receiving damage from a hostile mob you will also be knocked back. The resulting disorientation and loss of control should not be underestimated, as it is possible to be knocked back over a cliff or into lava, both of which are potentially fatal.

Players can also be nudged by neutral mobs walking into them. The push is not nearly as powerful as a hostile mob's knockback, but can still send the player off of a cliff or into lava. Knockback can also be caused when a player throws a chicken egg or a snowball at a mob, useful for making traps. As of Beta 1.8, sprinting while attacking a mob causes extra knockback. Players/Mobs riding an entity (typically a boat, a minecart or a pig) never receive any knockback when attacked.

Natural Damage
Besides mobs, players can take damage from several other events in Minecraft.

Lightning Damage
As of Minecraft 1.0.0, Lightning will do two damage, even through armor. Lightning strikes on the player are very rare, and only occur during thunderstorms.

Fall damage
You receive damage when falling from certain heights. The amount of damage received depends on the total height of a drop, and it is possible for a player to die upon falling to the ground. Armor does not reduce fall damage [Except for boots with the Feather Falling or Protection enchantments].

Fall damage can be calculated using this formula:

FD = number of blocks - 3

In other words, falling 4 blocks causes damage. From 5 blocks, damage. From 6 blocks, points are lost and so forth with, assuming full health, a 23 block fall being fatal (23 - 3 = 20 damage = 10 hearts of damage).

Mobs (other than chickens, ghasts, snow golems, blazes, magma cubes, iron golem, ocelots and, presumeably, the ender dragon) suffer fall damage as well.

In some cases, it is possible to avoid falling or otherwise survive a fall. Falling damage is only dealt after a height of three blocks.


 * Sneaking (default ) will prevent you from falling off most blocks.
 * Landing in Water will reduce fall damage. Depending on the height of the fall, it needs up to 3 blocks of water to reliably nullify the fall damage; however, even 1 or 2 blocks may sometimes do so.
 * Moving into a Ladder's area of effect during free fall will reduce vertical velocity to normal ladder descent speed and no damage will be taken.
 * Moving into water during free fall will also reduce velocity.
 * Move passive Mobs away to avoid an unpleasant push to your death.
 * Previous to Beta 1.6, Riding in a Minecart, Boat or on a Pig will allow you to leave the scene unhurt (though in the case of riding a pig, the pig will sustain fall damage. 1.6-on results in the same damage as you would falling. Also, if you fall while in a Minecart, water makes no effect on falling speed or damage. You will fall through as if nothing is there.
 * It is dangerous, but sometimes useful, to descend cliffs by walking off a cliff while in a boat. Exit the boat before impact, and you will only take damage for the distance fallen since exiting the boat.
 * Jumping counts as falling for 1.5 blocks, therefore adding to your total fall damage, so keep this in mind when trying to avoid fall damage.
 * Don't dig directly downwards without knowing what is underneath. Empty caverns are randomly placed around the world, and it's quite possible to fall into them (perhaps from a great height, or even onto a Dungeon or Lava).
 * Don't attempt to jump gaps across long drops. Instead, sneak to the edge of your current platform, and you will be able to place a block beside it; in this way, bridges can be constructed safely (so long as you aren't trying to place a gravity-affected block such as Sand or Gravel underneath yourself).
 * With good timing, you can place a block on the ground under you while falling. This will only reduce damage by, but will come in handy if you need to fall 4 blocks, as it will prevent all damage. If a vertical surface is available, a block can be placed on that as well with practice.
 * If falling next to a wall, emptying a bucket of water against the wall a few blocks from the ground can often save your life.
 * Wearing armor that is enchanted with feather falling or protection reduces fall damage based on the level of the enchantment.
 * Throwing an Ender Pearl and teleporting will reset your velocity, and you will only take damage from the pearl . This works best if you throw the Ender Pearl directly at the ground below you to guarantee the pearl hits the ground before you do.

Drowning


When a player runs out of air underwater, they will start drowning and will take approximately /sec. Mobs can drown as well, though they usually do not, as all mobs (besides iron golems and slimes) attempt to swim upward when in water.

While mining, consider keeping at least one placeable solid block ready somewhere on your toolbar (such as Dirt or Cobblestone) for quick access. If you mine into a spring (or worse, the ocean), you should be able to place the block in the hole to prevent drowning.

If you place a torch on a vertical surface next to you at head height whilst underwater, you create an air bubble which lasts for the split second it takes the water to destroy the torch, thus refilling your oxygen meter without resurfacing. Ladders, signs, fences, trapdoors, doors and sugar cane can create permanent air bubbles underwater. You can also scoop up some water with a bucket to achieve the same effect, or destroy the block directly above you, if there is one.

When drowning your oxygen goes down and eventually your hearts while under water.

Suffocation
Suffocation is when a player or a mob is unable to breathe due to his upper half being inside of a block. They will lose every half-second. Due to sand and gravel falling, it can easily cover the player. In first person mode, the player's screen will be blackened when suffering from this condition thus disabling them to see what is happening. In third person mode, the view will automatically switch to first person mode. As of the Beta 1.6 update, however, when a player's upper half is covered, the player is moved to the nearest empty space to stop them from suffocating.

When inside a block, the player can easily step out of it as the blocks do not prevent their movement.

The usual ways to get one's head inside a block are:


 * Sand or Gravel falling into the space the player or mob occupies.
 * Riding a Boat or Minecart into a one-block-high space.
 * Riding a pig into a two- or one-block-high space.
 * Standing where a tree just grew from a sapling.
 * Standing where a huge mushroom just grew from a mushroom.
 * Walking near a Redstone Repeater occasionally causes the player to be pushed down a block, especially if the ceiling is only two blocks above the floor. If there's exactly one empty space below the block, you'll fall to the level of this space and thus suffocate from the block covering your upper half.
 * Saving and reloading also occasionally causes the player to be pushed down in the same way as with Redstone Repeaters. If this happens while you are standing on bedrock, you might be unable to get out (without dying) due to bedrock being unbreakable.
 * Throwing an Ender Pearl into a one block space

It's worth noting that the player will not suffocate in glass, or indeed in any transparent block. Leaves from a grown Sapling will not suffocate you, even if you're on Fast graphics (which makes leaves appear solid).

Starvation
When the food bar reaches zero, the player will take damage every four seconds. The player stops taking starvation damage when the player eats or the health bar drops to on easy mode or  on normal mode. In hard mode, the damage will not stop until the player either dies, or eats something.

Cacti
Touching cacti will cause a player or mob to take damage, and rapidly continue taking damage if they continue to stand next to/on it.

Lava
By far the most dangerous natural occurrence (except for the unlikely case of a player falling into the void), players and mobs will take damage from contact with Lava extremely fast ( per hit), and stay on fire even if they exit it ( point per hit for 15 hits ( total damage) or until extinguished with water). If players do not have a water source available they will die quickly.

While mining, consider keeping at least one placeable solid block ready somewhere on your toolbar (such as Dirt or Cobblestone) for quick access using your mouse wheel. If you mine into a lava pool, you may be able to place the block in the hole and so prevent burning. It is possible to keep a fire-resistance potion at all times so you can prevent from dying in lava, although if you fall in the lava, you won't be able to use the potion in time. Instead, try using a splash potion of fire-resistance.

Poison
Cave Spiders will inflict poison status to players when they are bitten (only in normal and hard difficulty). Eating a Spider Eye or drinking/being hit by a potion of poison will give the same result. While poisoned, the hearts in the health meter turn from red to an olive yellow and continually damages the player by per second until the poison wears off. The poison itself cannot kill the player, but it can leave them open to attacks from other mobs or damage from the environment, possibly killing the player quickly. However, since Beta 1.9 Pre-release 4, poison can be cured by drinking milk from a bucket.

Damage immunity
After sustaining damage from any source, a mob will turn red in color for a short period of time. During this period, any other incoming damage will not be counted against the mob's total health. For instance, if you attack a mob with a Bow repeatedly hitting the mouse button, the bow's rate of fire will exceed the mob's allowable rate of incoming damage, and several of the shots will not damage the mob even if they land. Arrows that don't deal damage to a mob are reflected off of it onto the ground, and possibly, from a close range, back at the player (resulting in damage). However, if a mob or player is recovering from damage and then receives higher damage, it gets counted. Players are also subject to damage immunity.

Armor


Armor is a craftable item that can be worn in Minecraft's survival mode and survival mode multiplayer that reduces damage to the player while also decreasing the armor's durability. Armor can currently be crafted out of Diamond, Iron, Gold, fire and Leather.


 * Zombies and Skeletons would occasionally wear armor in Survival Test. This armor, however, did not alter any of their stats, and was purely superficial.
 * Chain Armor is also craftable, but only by using fire blocks, which cannot be obtained without inventory editing or mods.

Death


Death occurs when all of a player's hit points are depleted. A "You died!" screen will appear with the player's score displayed (before Beta 1.9pre2, it had &e0 as the score), and the player has the option to respawn at the spawn point (either the last bed the player slept in or their default spawn point) or return to the title Menu. In Hardcore Mode, the player cannot respawn and the world will be deleted. Any items and/or blocks that were in the player's inventory are dropped from their head and scattered around the spot where the player died. If they come in contact with dangerous blocks - like lava, fire or cactus blocks - they will be destroyed. Otherwise, according to Notch, "they decay after five minutes, except if the chunk is unloaded, in which case they last forever". The player will also lose any accumulated levels.

Mobs fall sideways to the ground when killed, as shown in the image. If lightning kills them, the lightning charge will stay until the mob disappears.

History
In Indev before suffocation was implemented, players that were covered by blocks could see through dirt and stone. Suffocation was added after Notch discovered that players were abusing this exploit to find underground caves and hollowed carvings. The patch added suffocation damage and making the player unable to see anything when experiencing it. However, this glitch is not completely fixed and is still possible to be done even in the existing version of the game.


 * July 9, 2010 (Alpha 1.0.4) - Players no longer suffocate when riding in a minecart.


 * November 10, 2010 (Alpha 1.2.2) - Players no longer suffocate when they get out of a minecart while inside a two block high tunnel. The same applies when disembarking a boat. This does not apply to multiplayer; you will still suffocate when leaving said minecart/boat.


 * April 20, 2011 (Beta 1.5) - Unarmed damage was increased from to.


 * September 14, 2011 (Beta 1.8) - Unarmed damage was decreased from to.


 * September 29, 2011 (Beta 1.9) - Mobs can now have armor points


 * Earlier in Survival mode, eating a Red Mushroom would deal the player of damage because they were poisonous.
 * In 1.0.0, the sound of the player taking damage was changed from a masculine "oof! or UGHH!" sound, to a strange crunch. This sound is used for all types of damage except for falling and drowning, which adds more of a cracking sound simulating broken bones even if the damage is light (e.g. punch damage).
 * These were changed to remove the restriction that all avatars have a male voice, regardless of the gender of the character depicted in the skin.


 * June 21, 2012 (snapshot 12w25a) - removed the downwards knockback while drowning.

Trivia

 * A bucket of lava is arguably the most efficient weapon in the game, as it doesn't use up durability, does very fast damage, and slows enemies in their tracks. The only downside is that most of the time the mob's dropped loot will disintegrate in the lava. It may also cause nearby trees or wooden buildings to catch fire, possibly even starting vast fires, also it may backfire if the user is hit by the lava and is messy to clear up after use.
 * Transparent blocks will not cause suffocation. As a result, placing a slab above a minecart track can be used to make a barrier through which carts can be ridden without allowing mobs (other than 1 block high Chickens, Pigs, tiny Slimes, Silverfish, Cave Spiders and Wolves) to wander in.
 * Using a trapdoor functions similarly, in addition to being able to open the door to pass through on foot.
 * Players deal Critical hits when falling (losing altitude).
 * When you die and while you are dead your skin reverts to the default skin. This can be seen by falling from a great height or burning in lava, and checking your inventory moments before death.
 * if you use a Piston to push a block of Glowstone onto your head, and there are no empty spaces around you, you can see around underground for close to 30 blocks in some directions.