A course is a continuous horizontal layer of similarly-sized building material one unit high, usually in a wall. The term is almost always used in conjunction with unit masonry such as brick, cut stone, or concrete masonry units ("concrete block").
Stretcher - The typical course style, masonry units are laid with their face parallel to the wall and the long dimension outwards. Header - a course with the face of the unit parallel to the wall, and the small dimension outwards, often used to interlock two adjacent wythes.
Rowlock - A course with the long dimension parallel to the wall and the small face looking outward. Most commonly used at the topmost course of a wall, and above or below openings within it.
Soldier - Used mainly for decorative purposes as its upright nature does not lend itself to the compressive strength of a masonry unit. The longest dimension is vertical, with the large face perpendicular to the wall.
Sailor (rare) - Decorative, with the longest dimension of the brick vertical and the widest dimension parallel to the face of the wall.
Shiner (rare) - Decorative, with the longest dimension of the brick horizontal and the widest dimension parallel to the face of the wall.
A string course or band course is a thin projecting course of brickwork or stone that runs horizontally around a building, typically to emphasize the junction between floors, or just below the eaves.