A pile is a wedge-shaped charge issuing from the top edge of the field and ending just above the base point. Sometime a pile is drawn so that it reaches all the way to the opposite edge of the field. This is blazoned a pile throughout . It is occasionally found in period armory, and is an artistic variation. For medieval heraldic art, the pile should be about 1/2 the width of the field. Modern heraldry often uses a wider pile--about 3/4 the width of the field--and that version is occasionally found in late-period English arms.
Similar wedges in various orientations (inverted, bendwise, fesswise) can be found in period armory, notably in Germany. They are grossly overused in Society armory.
Piles are generally not charged in period armory. This is a common mistake in Society armory. If they are charged, they should be charged with simple, common charges that can be drawn fairly small. One should never place a charge below a pile (i.e. between the point and the base of the field) or, as is more commonly done in the Society, above a pile inverted. Placing a charge in this position forces the pile to be drawn too short.
There are three field divisions which have appearances somewhat similar to a pile, but they are quite different: per chevron, chapé, and chaussé.
The division per chevron begins at the flanks, one third to one quarter of the way up from the base. The point should be acute (less than 90 degrees) and should reach nearly to the top edge of the field. If the field is charged, charges are best placed in dexter chief, sinister chief, and/or base. Charges should not be placed above the point of the division. When blazoning the division, the upper tincture is named first.
The division chapé (caped) is similar to per chevron, except that the point of the division touches the top edge of the field. If the field were a rectangle, then the division chapé should be drawn by connecting the lower two corners to the middle of the top edge. This is a fairly rare division in period, found mostly in France, and some heraldic writers treat it as a member of a distinct class of field treatments called encroachments. The upper parts of the field are rarely (if ever) charged. When blazoning, the lower tincture is named first: Gules chapé argent means that the lower (larger) piece of the field is red and the upper two triangles are white.
The division chaussé (shod) is the inverse of chapé: It is formed by connecting the upper two corners to the base point. The two flanks created by these lines are the chaussé. They are rarely charged. In blazoning, the central part of the field is named first: Gules, chaussé argent means that the middle (upper and larger) piece of the field is red and the two lower flanks are white.