Kippot
What is a Kippah ? The Kippah, or Yarmulke, is a head covering worn primarily by Jews. Circular and rounded, to fit the top of the head, it can be crocheted (in Hebrew these are called kippot serugot), sewn from silk, satin, velvet or other fabrics, some are large and embroidered, and they can be made in any color or pattern. Some of the most common, depending largely on the community buying them, are white silk, black velvet, and patterned crocheted (or woven) Kippot. Found in Judaica stores worldwide as well as in specialty Kippah stalls in Jerusalem and the like, Kippot can be worn nearly all the time, although some communities wear them only outdoors, or on special occasions and at the synagogue.
Why do we wear a kippah? We wear a kippah to differentiate ourselves from those around us and do a Kiddush Hashem by acting admirably when visibly Jewish. The talmud teaches: "Cover your head in order that the fear of heaven may be upon you," and according to many sources, a man should not walk more than four cubits with his head uncovered. There is debate between the Jewish communities as to who should wear a kippah and when it is necessary, the most lenient point of view only requiring it during prayers. Most Shuls and synagogues keep some extra kippot handy for visitors. Women may wear kippot, but are not obligated to in any community, whereas boys and men often wear them from the age of three years old.
You may have heard the Kippah referred to under several different names. It can be called Kippah, Yarmulke, or Skullcap. There is no difference except in the origin of the words. While Kippah is the Hebrew word for the head cover, Yarmulke is the Yiddish word, and skullcap is the English term given to the garment.
Different communities in Judaism tend to prefer different styles of Kippot. The Reform movement and conservative communities often prefer white satin kippot, while black velvet Kippot are the preference in ultra-orthodox and Hassidic circles. Colorful woven or crocheted kippot, as well as basic sewn fabric or suede Kippot, are used by many, especially the modern orthodox and Zionist communities. A full-headed white tasseled Kippah can be found with or without words written on it around Jerusalem and in a (Na Nach) subgroup of the Breslov Hasidim, and the full headed Sephardic embroidered kippah is often used for children as well as the Bukharan community that introduced it.