This tool is used to connect blocks. To do so, move the mouse pointer to a block input or output and press the left mouse button. Keep the mouse button pressed, drag the mouse pointer from your selected source terminal to the target terminal. Now release the mouse button to anchor the connecting line to both terminals. While the connecting line is being drawn, it is shown as a straight line between the first terminal and the mouse pointer. Once it is anchored, it appears as a combination of horizontal and vertical lines, which can be manipulated using the selection tool.