Line of sight, sometimes written line-of-sight or abbreviated to LoS, is the visibility (that is, who can see what) on the playing field in wargames and some role-playing games (RPGs). Many abilities can only be used on entities within a character's line of sight.
In some games, miniature figures are used to determine line of sight. Many wargames use counters to represent units and determine line of sight. A common technique is to hold a length of thread between two counters. If the thread, held straight, doesn't encounter any obstacles, the line of sight is valid.