Final answer:
In sewing and embroidery, the technique that forms an "X" is known as a stitch, specifically the cross stitch, which is fundamental to embroidery and remains a valued craft.
Step-by-step explanation:
In sewing & embroidery, the form that creates an "X" is referred to as a stitch. This type of stitch is most commonly known as the cross stitch, which is a popular embroidery technique used for decorative purposes and to create designs on fabric. The cross stitch is achieved by bringing the needle and thread up from the back of the fabric to the front, crossing over to form a diagonal line, and then crossing over again to create an 'X' shape on the fabric. This technique is a fundamental skill for embroiderers and is often one of the first stitches learned by beginners. Embroidery has a rich history, with textiles often reflecting the trading relationships and cultural traditions of a region, such as the use of wool and cotton in Andean textiles. Moreover, since the industrial revolution and the advent of sewing machines, the creation of textiles has greatly evolved, but hand embroidery like cross stitch remains a valued artisanal craft.