What does Boxing Day have to do with boxing?
"embroidery specimen by a beginner to show skill," 1520s, from sample (n.); earlier "pattern, model, example to be imitated" (early 14c.). The connecting notion is probably "piece of embroidery serving as a pattern to be copied, or to fix and retain the pattern." As "a collection of samples" from 1912.
embroidered panel of linen on which various types of stitches are demonstrated. The earliest extant European examples date from the 16th century. The original purpose of the sampler, in the period before embroidery pattern books became available in 1523, was to demonstrate a repertory of embroidery stitches that might be used in the future. In the earliest dated specimen (1598), different motifs are arranged in a somewhat random fashion on linen. In the 17th century both the function of the sampler and its appearance changed. A school exercise rather than a repertory of stitches, it was dated and signed with the name of the pupil and sometimes of the teacher as well. It was, moreover, a work of art, executed as an end in itself. In the 17th century it was usual to work rows of stitches across the width of a long, oblong band; from the early 18th century onward, samplers tended to become square in shape and to show an overall design for arranging the component stitches, though the old form also persisted. Texts were embroidered, framed with a symmetrical arrangement of motifs; scenes with houses and people were worked, approximating embroidered pictures; and, in the latter part of the century, maps, almanacs, and the like were also represented. Nineteenth-century samplers continued on similar lines, mainly on canvas.