According to the Dictionary " Embroidery is the Art of working ornamental designs upon cloth or other material with a needle and thread ".
This type of work can be traced as far back as the Iron Age. As time went on embroidered clothing became a symbol of wealth. You can find it done on early clothing, handkerchiefs, pillows and of course samplers. Even today, people love to embroider things with the brightly colored threads either by following a stamped on pattern or making their own designs free-hand. Of course, there is also Cross-stitching that also dates back to the early 1700's where you have a pair of diagonal stitches of the same length that cross each other in the middle to form an X. Above is an example of a towel done in the mid to late 1900's using cross-stiching as well as others stitches.
Here is one type of Embroidery: Crewel
Crewel is a type of decortive surface embroidery featuring stylized shapes inspired by nature, including plants, animals, trees and sometimes people. The designs are arranged in a fanciful, flowing or repeating patterns.
Usually worked in single or two ply crewel wool or other wool embroidery threads on a heavy linen or twill ground, this type of embroidery is worked in a variety of surface embroidery and filling stitches, but is also commonly found worked solely in chain stitch, as shown in the example in the photo.