The popular term "West Coast Offense" is more of a philosophy and an approach to the game than it is a set of plays or formations. Traditional offensive thinking argues that a team must establish its running game first, which will draw the defense in and open up vertical passing lanes downfield (i.e., passing lanes that run perpendicular to the line of scrimmage). Bill Walsh's West Coast Offense, however, differs from traditional offense by instead emphasizing a short, horizontal passing attack to help stretch the defense out, thus opening up running lanes. The West Coast Offense as implemented under Walsh features precisely run pass patterns by the receivers that make up about 65% to 80% of the offensive scheme. With the defense stretched out, the offense is then free to focus the remaining plays on longer throws (more than 14 yards) and mid to long yard rushes.
