Technical Drawing
Technical drawing (also known as drafting or engineering drawing) is a precise and detailed form of drawing used to visually communicate how something functions or is constructed. It is commonly used in architecture, engineering, manufacturing, and design.
Here’s a breakdown of key terminology in technical drawing, especially related to geometric drawing:
🔹 Basic Geometric Drawing Terms (English)
| Term | Definition |
|---|---|
| Point | An exact location in space with no dimensions. |
| Line | A straight one-dimensional figure extending infinitely in both directions. |
| Line Segment | A part of a line between two endpoints. |
| Ray | A line that starts at a point and extends infinitely in one direction. |
| Angle | Formed by two rays (or lines) with a common endpoint (vertex). |
| Vertex | The common endpoint of two or more rays or lines forming an angle. |
| Plane | A flat, two-dimensional surface that extends infinitely. |
| Circle | A set of points equidistant from a central point. |
| Arc | A portion of the circumference of a circle. |
| Radius | A line from the center of a circle to any point on its circumference. |
| Diameter | A line passing through the center, connecting two points on the circle. |
| Chord | A line segment connecting two points on a circle, not necessarily through the center. |
| Polygon | A closed figure formed by a finite number of straight line segments. |
| Triangle, Square, Hexagon, etc. | Types of polygons, named by the number of sides. |
| Parallel Lines | Lines in the same plane that never intersect. |
| Perpendicular Lines | Lines that intersect at a 90° angle. |
| Tangent | A line that touches a curve or circle at exactly one point. |
🔹 Technical Drawing-Specific Terms
| Term | Definition |
|---|---|
| Orthographic Projection | A method of representing 3D objects in 2D using front, top, and side views. |
| Isometric Drawing | A 3D representation where axes are equally spaced at 120°. |
| Section View | A view showing the interior of an object as if it were cut. |
| Dimensioning | Adding measurements to a drawing. |
| Scale | The ratio between the drawing size and actual size. |
| Hatching (or Crosshatching) | Patterns used to indicate material or cut surfaces in section views. |
| Title Block | Contains information about the drawing (e.g., title, scale, date, drafter). |
| Tolerance | The permissible limit of variation in a dimension. |
| Hidden Line | A dashed line representing edges not directly visible. |
| Center Line | A line representing the center of a circle or symmetrical object. |
| Leader Line | A line that connects a note to a feature on the drawing. |
