A Life bar is used in many video games to show a character's health and how close the player is to failure ('death', being knocked out, etc).

A typical life bar is a horizontal rectangle which starts full of colour. If damage is taken or mistakes are made, the coloured area gradually shrinks to nothing.

In some games (e.g. the fighting game Street Fighter), the bar doesn't immediately decrease when damage is taken. Instead, an area representing the damage is marked, and the life lost slowly drains away. This is useful in assessing the amount of damage caused by a particular attack.

Some games use an incremental bar, composed of many smaller bars. Each attack will remove a certain number of these bars. This system is used in the Mega Man series.

A variation is starting with the bar empty or half-full, and being able to fill it by successful play. This system is common in rhythm games like Dance Dance Revolution.