Line-drawing tool is a type of tool used to draw straight lines. The two most common tools used for this purpose are a ruler and a STRAIGHTEDGE. A ruler is a four-letter tool that is used to measure distances and draw straight lines. It is usually made of wood, metal, or plastic and has markings on it to indicate measurements. A STRAIGHTEDGE is a twelve-letter tool that is used to draw straight lines. It is usually made of metal or plastic and does not have any markings on it. Both of these tools are used to draw straight lines and can be used in a variety of applications.