As you create or move objects, you can use Ortho mode to restrict the cursor to the horizontal or vertical axis. The orthogonal alignment depends on the current snap angle, UCS, or isometric grid and snap setting. Ortho works with commands that require you to specify a second point. You can turn Ortho on and off at any time during drawing and editing. You can use Ortho not only to establish vertical or horizontal alignments but also to enforce parallelism or to create regular offsets from existing objects.
By imposing orthogonal constraints, you can draw more quickly. For example, you can create a series of perpendicular lines by turning on Ortho mode before you start. Because the lines are constrained to be parallel to the horizontal and vertical axes, you know that the lines are perpendicular.
As you move the cursor, a rubber-band line that defines the displacement follows the horizontal or vertical axis, depending on which axis is nearest to the cursor. AutoCAD LT overrides Ortho when you enter coordinates on the command line, use perspective views, or specify an object snap.
For drawing or editing objects at angles that are not parallel to the horizontal or vertical axis, see Using PolarSnap.