A Wide midfielder (Left midfielder or Right midfielder) is a midfield player who has a role balanced between attack and defence, similar to that of central midfielders, but they are positioned on the side of the field, closer to the touchlines of the pitch.
Wide midfielders roles are to control the ball on the side of the bitch, cross the ball into opponent's penalty box and make goal scoring opportunities for their forwards. They also are asked to help for defending. Usually, Wide midfielders are positioned on the pitch based on their preferred foot - Left-footed midfielders to be positioned as Left midfielders, and right-footed as Right midfielders.
Wide midfielders positioned on the right side of the pitch are normally called Right midfielders (RM). The ones on the left side are called Left midfielders (RM).
Wing-half is the classic term for this position. Wing-half is basically a CDM who participate mostly in defence near the side of the pitch.
In FIFA and FIFA Mobile, the following positions are available for Wide midfielders: