Types of Damage
Environmental damage is damage that cannot be configured in any way by a place creator. The only type of environmental damage that currently exists in ROBLOX is world border damage, which causes a ROBLOXian to die if they go too far outside the ROBLOXian world. The most common example of this is when a ROBLOXian falls off a brick into the bottom of the ROBLOXian world. After a few seconds, the ROBLOXian will die. However, the max distance a player can fall down can be edited by developers. The max is -5021.
Local damage is damage that can be caused by elements which can be modified by a place creator. Currently, only scripts can create damage. Local damage can be effected on humanoids by scripts by either appl`ying the TakeDamage() method, or by manually setting a humanoid's health to a level lower than it was before. However, doing TakeDamage() will not damage the humanoid if there is a ForceField present in the character. If the health is set to 0 or less, the .Died() event will call. For example, say there was a character named Telamon within the workspace. To damage him by 50HP, we could either do this:
workspace.Telamon.Humanoid.Health = workspace.Telamon.Humanoid.Health - 50