Pattern and symmetry are seen in woven textile designs because the looms on which they are woven depend upon the raising or lowering of threads in repeated sequences. Because pile rugs are constructed on simple frame looms, one knot at a time, they are not dependent upon the design repetitions imposed by the more complicated textile looms. However, some of the rugs do contain repeat patterns. Why is this?
- Most importantly, pattern was a deliberate aesthetic choice;
- The rugs were created in collaboration with textile designers, and the existing textile tradition incorporated pattern, both in woven and printed textiles;
- Pattern is a way of organizing a design. Before a rug was started, its size, design, and pattern repeats had to be taken into account. Otherwise, for example, the weavers might run out of one color of yarn, or a design on one end of the rug might not match the design on the other side.
The weaver or weavers sitting at a loom probably had a cartoon, or drawing, to follow for the field of the rug, and possibly small designs plotted on paper for the border. These designs could have been created by manuscript illustrators, or they could have been copied from an existing rug. For reference, only the basic pattern unit would have been needed, with instructions on how to repeat it, reversed, flipped, or alternated with another unit for variety.
Field designs
The field is the center portion of the carpet, usually the largest area. Its design can be pictorial or based on an allover pattern, but it is always flat--flower petals may overlap or animals may be shown in three dimensions, but there is no attempt at creating the illusion of deep space. Examples of pattern and symmetry in the field of the carpet are given in the following carpets:
Lattice: The curving lines of this grid break the surface of the rug into small sections that can organize individual motifs, in this case, fantastic blossoms.
Rows: All these flowers are oriented to the same direction.
Pattern units composed of many single motifs: This landscape carpet shows a pattern unit of flowers, trees, and animals, and it is repeated 3-1/2 times over the field of the carpet. With each repeat the unit is flipped horizontally. 
Bilateral symmetry: The entire field design of this niche carpet is bilaterally symmetrical; that is, if a line were drawn down the center of the rug from top to bottom, the blossoms, leaves, and stems on one side of the design would be a mirror image of the other. 
Bilateral symmetry: Although the design of this niche carpet is made up of a multitude of small-scale elements, they are all organized according to the rules of bilateral symmetry--one side is a mirror image of the other.
Patterns in the borders of the carpets also vary in their design, orientation, and use of symmetry. Some examples are:
- The border of the landscape carpet is a pattern of six-pointed stars and arabesques.
- A row of cypress trees alternating with flowering plants frames the lattice carpet. The trees are arranged so that the bottom, of the trunk, always touch the inside field of the carpet.
- Scrolling flowers wind around the border of the niche carpet.
Guard bands are the long, thin areas of pattern that separate the field of the carpet from the border, or they may run along the edge of the border. They usually employ zigzags, simple repeated shapes, or wavy floral scrolls.
Guard bands are useful in identifying the origin of a particular carpet. While field and border designs traveled freely from area to area, the pattern of the guard bands usually followed local conventions.
