A base or foundation: Called the warp , the base is made of a single continuous resistance thread , most often cotton or silk , which will be selected in pairs onto the weaving loom , one after the other by the weaver while weaving.
The pile: On each of the pairs of warp threads, a woolen thread of several strands or silk thread is tied into a knot or into an interlacing ). The loose end from the velvet, called the “pile”.
The knots: Are applied one by one on the same row, then row after row. They are of different colors to create precise pattern following a design prepared on a sheet of graph paper onto which the place of each knot with its specific colors is plotted.
The weft: The weft consists of a very fine but resistant colored cotton thread called “the fine one” in Persian . The weft thread is delicately passed with a comb through the crossing line of the two half sheets of the wrap in order to wind around each wrap thread .the weft thread zigzags from one wrap thread to another , from the front to the back, then from the back to the front along the row thus maintaining the pairs of wrap threads tied together.
A Strengthening Threads: this thick cotton thread is inserted in each row before the weft thread and reinforces the base of the carpet. In Persian it is called” The thick one” and is passed by hand or with a metallic hook through two sheets of wrap threads below the crossing line. It is firmly packed down with a steel comb . Its role is to set the knots between the two wrap threads and to give body and the strength to the base of the carpet which will lie on the floor . The strengthening thread is often wrongly assimilated to a weft thread.