Let's start at the very beginning...a very good place to start!
The most basic elements of form are point, line, plane, and volume. It is important to understand them as each one is created from the previous (e.g., a line is created by a point in motion). A more in depth explanation below:
POINT
Point can be defined as a position in space. It has no dimension and therefore no length, width, or height. It shows no movement or direction- it is static. However, point can be expressive. For instance, a point located in the middle of a field creates a stable, balanced, and organized environment. In contrast, a point that is off-center shows aggression and tension in its environment.
The picture of the bedroom below illustrates how effective the use of point can be in creating a successful interior space.
Imagine the black mirror as a point, and the wall its field. Because the point is centralized, a feeling of balance, simplicity, and peacefulness is created in the room. Also, points are marking the ends of the lines created by the chains coming from the fan which show another property of point. Along with marking the ends of a line, point also marks the intersection of two lines, the corner of a plane or volume, and the center of a field. With that being said, you can find points everywhere: the corners of the ceiling; the top of the lamp/the finial; the corners of the windows; and so on. Although the points are static themselves, the repetition of this element in a room creates visual rhythm which keeps your eye moving in the space.
Photo by Roger Davies, from the January 2011 issue of Southern Living magazine.
The diagram below illustrates how point relates to its environment. Some points are more visually dominant or mark important lines, planes, or volumes in a space.
LINE
Line is created when a point is extended or as Paul Klee stated, "A line is a dot that went for a walk". Line can be literal or implied. Lines have length, direction, and like point, position. Also like point, lines can be expressive. Horizontal, vertical, diagonal, thick, thin, curved, and every other type of line each have descriptive properties and visual abilities. For example, the use of strong horizontal lines in a space would emphasize calmness and rest.
The picture below shows how lines direct and create harmony in a space.
First, the diagonal lines created by the edges of the countertops draw the eye from the kitchen into the dining area. Diagonal lines are very active and create movement. And in this case, they define the edges of the pathway to the next room. Second, the repeated strong verticals across the kitchen (the cabinets on the left, the doors, and transom window)merge with the strong verticals in the next room, creating unity between the rooms... which, of course is especially important in interiors.
Photo by Laurey W. Glenn from the April 2010 issue of Southern Living magazine.
The diagram below shows how line can create direction and connection in a space.
PLANE
A plane is created when a line is extended in another direction giving it width. It has the properties of line (length and position), but also has width, shape, surface, and orientation. Having both length and width, planes are two-dimensional. Shape is usually the key to identifying a plane. Planes in general define the boundaries of a volume.
The picture below is a great example of planes and how the create boundaries.
Each facet of each shelf, the surface of the picture frame, and the side of the book are all planes. Not only do these opposing planes create interest on the wall of this room, but they also form spaces. For example, if you imagine the shelves simply as planes, the bottom shelf/plane, the middle shelf/plane, and the wall plane create a space in which the books and accessories can occupy. This idea can be carried through to interior rooms. In architecture, there are three types of planes: Overhead Planes (such as ceilings); Wall Planes; and Base Planes (floors). These planes create and define the spaces in which we occupy.
Each facet of each shelf, the surface of the picture frame, and the side of the book are all planes. Not only do these opposing planes create interest on the wall of this room, but they also form spaces. For example, if you imagine the shelves simply as planes, the bottom shelf/plane, the middle shelf/plane, and the wall plane create a space in which the books and accessories can occupy. This idea can be carried through to interior rooms. In architecture, there are three types of planes: Overhead Planes (such as ceilings); Wall Planes; and Base Planes (floors). These planes create and define the spaces in which we occupy.
Photo by Laurey W. Glenn from the January 2010 issue of Southern Living magazine.
The diagram below simplifies the idea of opposing planes.
VOLUME
Volume is created when a plane is extended in an opposing direction. It too has characteristics of length, width, surface, orientation, and position, but also has depth which creates form and space. It is the only three-dimensional element of the primary elements. Volume can either be a solid mass (such as a pillow) or a space contained by planes (a swimming pool). In interior design, you must relate the two types together to understand the forms and spaces more completely.
The picture below suggests the concept of spaces being created within other spaces, an idea that is a big part of interior design! But it also further clarifies what volume is.
Since volume is the most complex of the primary elements and contains each of them, you can see the other three in this volume: The perpendicular planes of glass along with the base plane define the boundaries that contain the orchid plant; The metal edges of the volume represent the lines that are created where the two planes meet; And, the corners of the container are points where several lines and planes come together.
Photo by Tria Giovan from the October 2009 issue of Southern Living magazine.
http://www.southernliving.com/home-garden/decorating/craftsman-style-home-decorating-ideas-00400000064639/page13.html
The diagram below illustrates a object within a volume.
I hope this has helped in understanding point, line, plane, and volume!
