This is one of the eleven basic knots of traditional Chinese knotting, a craft which began in the Tang and Song Dynasty (960-1279 AD) in China. The Chinese and Japanese names for this knot are based on the shape of the ideogram for the number ten, which is in the shape of a cross.The Ashley Book of Knots, first published in 1944, says: "A decorative Chinese Loop. This is commonly employed as a Lanyard Knot. It is handsome and secure." In recent years, it has become popular with members of the Scout and Guide movements for tying their neckerchieves instead of using a woggle.
A Scout neckerchief tied with a friendship knot; the purple/yellow neckerchief below it shows the same knot viewed from the back.