A kippah or yarmulke (also called a kappel) is a thin, slightly-rounded skullcap traditionally worn at all times by Orthodox Jewish men, and sometimes by both men and women in Conservative and Reform communities during services and other religious rituals. Its use is associated with demonstrating respect and reverence for God.

hover">http://www.himfr.com/buy-hover_button/">hover buttonThere are different proposed etymologies for the word yarmulke. According to most mainstream etymologists, it is a Yiddish word deriving from the Polish word jarmulka, meaning "cap", ultimately possibly of Turkish origin.[2]

Others propose that it is derived from an Aramaic phrase, yarei malka, meaning "fear of the King [i.e. God],"[3] or from the Hebrew, ya'arei me'Elokai, "those who tremble before the Lord."

The Hebrew-language equivalent, kippah , plural kippot , actually means "dome." The Gothic word kappel (cf. chapel) still exists in the Yiddish term today and survives in the Viennese dialect word kappl (hat). The equivalent of the Hebrew word is the French calotte and the Italian calotta, both referring to an architectural dome.

The sources for wearing a kippah are found in the Talmud. In Shabbat 156b it states: "Cover your head in order that the fear of heaven may be upon you." In Kiddushin 31a it states, "Rabbi Honah ben Joshua never walked 4 cubits (2 meters) with his head uncovered. He explained: 'Because the Divine Presence is always over my head."

As to the obligation of wearing a kippah, halakhic experts agree that it is a minhag (custom). The prevailing view among Rabbinical authorities is that this custom has taken on a kind of force of law (Shulkhan Arukh, Orach Chayim 2:6), because it is an act of Kiddush Hashem. From a strictly Talmudic point of view, however, the only moment when a Jewish man is required to cover his head is during prayer (Mishneh Torah, Ahavah, Hilkhot Tefilah 5:5).

Even this interpretation is in question; as recently as the 1600s, scholar David Haley of Ostrog, Ukraine, suggested that Jews should never uncover their heads in order to help distinguish them from Christians especially while at prayer.

According to the Shulchan Arukh, Jewish men are required to cover their heads and should not walk more than four cubits without a hat.[4] Wearing a kippah is described as "honoring God".[5] The Mishnah Berurah modifies this ruling, adding that the Achronim established it as a requirement to wear a head covering even when traversing less than four cubits,[6] and even when one is simply standing in place.[7] This applied both indoors as well as out.[8]

This ruling is echoed by the Kitzur Shulchan Aruch, a concise version of the Shulchan Aruch authored by Rabbi Shlomo Ganzfried.[9] He cites a story from the Talmud (Shabbat 156b) about Rav Nachman bar Yitzchok who might have become a thief had his mother not saved him from this fate by insisting that he cover his head, which instilled in him the fear of God.[9]

In many communities, boys are encouraged to wear a kippah from a young age in order to ingrain the habit.[10]

According to Rabbi Isaac Klein's Guide to Jewish Religious Practice, a Jew ought to cover his head when in the synagogue, at prayer or sacred study, when engaging in a ritual act, and when eating.

A Hasidic/Kabbalistic tradition states that the kippah reflects several ideas. One is that God covers us with His Divine Palm; indeed, the Hebrew word kaf means either "cloud" or "palm of the hand." The Hebrew letter Kaph is the first letter of the word kippah.

The kippah is traditionally worn by Jewish men. Observant Jewish women who have been married (including widows and divorcees) cover their heads more completely with scarves, hats, or wigs, but for a totally different reason. The tradition for women comes from a different source than that of men and originates from the laws dealing with the sotah (suspected adulteress; see Numbers 5), implying that a Jewish married woman should cover her hair under normal circumstances.[12] Today, some women ??mainly Reform and Conservative Jews ??wear a kippah. Some Jews wear kippot only while praying, eating, reciting a blessing, or studying Jewish religious texts.

In modern contexts, it is also common for non-religious Jews or even non-Jews to wear a simple kippah, or to cover their heads as a sign of respect, when present at Jewish religious services or at ostensibly Jewish sites, such as Yad Vashem and the Western Wall. Male Jews and non-Jews alike are asked to don a skullcap in the vicinity of the Western Wall, and returnable skullcaps are provided for this use.

Any form of head covering is acceptable according to halakha (Jewish law). There are no hard and fast rules on the subject, although the compact, lightweight nature of a kippah, along with the fact that hats for men have fallen out of fashion in the West over last few decades, may have contributed to its popularity. Kippot have become identified as a symbol of Judaism over the last century. Haredi men, who mostly wear large black cloth or velvet kippot, often wear fedoras with their kippot underneath. In the Hasidic community, this double head-covering has Kabbalistic meaning.

Many Muslims wear a kippah equivalent called a topi. The origin of this practice, and any other practice of men covering their heads with various head gear, is the general sunnah (or normative practice / example) of the Prophet Muhammad to cover one's head. Until more recent times, men in most Muslim societies were rarely seen without headdress of some sort. A taqiyah (cap) covers most of the head. Covering the head is seen by Muslims to transcend many religious traditions, confirming Muslim belief in the practice's Divine origin, as, according to Muslim belief, all Prophets of God preached the same basic message with varying cultural and social adjustments throughout time. Finally, the modern taqiyahs worn by Muslims are analogous to the kippot worn by observant Jews whether in the Middle East or elsewhere. The Jews of the Middle East probably picked up much of their clothing and head gear from the wider society in which they lived. Hence, no different from their Muslim neighbors and compatriots throughout time, the kippah can be seen as much a product of the Middle East and its diverse social fabric of co-existence as is its analog (in terms of head coverings), the taqiyah.

The doppa, a square or round skullcap originating in the Caucasus and worn by Kazan Tatars, Uzbeks and Uyghurs is another example of a Muslim skullcap. The doppa is derived from a Turkic, more pointed ancestral cap, which can be seen in some of the portraits of Jalaleddin Mingburnu.

Conservative Muslims in Malaysia, especially in the rural areas, are often seen wearing a thin kopiah, which looks almost exactly like the kippah in outward appearance.