In letterpress printing and typesetting, a composing stick is an instrument used to assemble pieces of metal type into words and lines which are later bound into a forme, set in a galley and printed. Some composing sticks had one adjustable end allowing the length of the lines and consequent width of the page or column to be set, with spaces of different sizes being used to make up the exact width. Other early composing sticks were fixed to the width of a newspaper column, when newspapers were still composited by hand.
The compositor takes the letter blocks from the boxes (compartments) of the type case and places them in the composing stick, working from left to right and placing the letters upside down with the "nick" to the top.
Composing sticks were manufactured by many companies, but notably by the H.B. Rouse company. They made composing sticks that were adjustable to the half pica, as well as a stick containing a micrometer that was infinitely adjustable. Some sticks were marked in agates as well, to aid in newspaper and advertisement composition.