directionshorizontal

Directionshorizontal is a term used to describe the component of direction that lies along a horizontal axis. It is a descriptive label used across disciplines such as mathematics, physics, computer science, and design to distinguish horizontal orientation from vertical.

In geometry, a direction is horizontal when its vertical component is zero. A direction vector (dx, dy) is horizontal if dy equals zero; the unit horizontal directions in two dimensions are (1, 0) to the right and (-1, 0) to the left.

In three-dimensional space, horizontal directions lie in the horizontal plane, typically defined as the plane perpendicular to the vertical axis. If y is vertical, horizontal vectors have dy = 0, taking forms like (dx, 0, dz).

Practical uses include projecting movements or forces onto a horizontal plane, such as leveling a drone's flight path, mapping routes on a flat map, or aligning user interface elements along the left–right axis.

In navigation and engineering, horizontal directionality informs design decisions and analysis, separating horizontal effects from vertical ones such as altitude or height.

Related concepts include horizontal versus vertical, projection of vectors, and directional components. The term directionshorizontal is often used informally or as a compound keyword in technical documentation or data schemas.