In USolver, arrows — also known as markers — can be added to either end of a line to visually indicate direction, flow, or emphasis. These markers come in various styles, including classic arrows, stop lines, circles, and more, giving users flexibility in how they convey meaning. You can customize the size and color of each marker to match the design or purpose of your diagram. Additionally, markers can be animated to show motion or progression, making them especially useful for illustrating dynamic systems or interactive visualizations.