There is no Biblical reason, but it is a custom, as a symbol to 'remember' the significance of Shabbat, and to 'keep' the laws of Shabbat, which are two things the Torah tells us to do on the seventh day of each week.
There is a prohibition against kindling a flame on Shabbat, so the rabbis instituted that one should always light candles before the Shabbat so that the house should not be devoid of light. Nowadays it is enough to simply turn on electric lights, but the custom to light actual candles still prevails, though it is of no halakhic significance.
The candles (usually two, though sometimes with an extra one for each child in a family) are lit in honour of Shabbat and to herald a sense of domestic tranquility (shalom bayit) which is maintained in the home until Havdalah - the conclusion of Shabbat when three stars are visible in the sky on Saturday night.
The two Challot used on Shabbat are called Lechem Mishneh (Double Bread or Extra Bread. This is to commemorate God having provided a double portion of manna to the Israelites on Friday to account for the fact that He would not provide on Saturday. (Exodus 16:4-5, 16:14-16)
One of the most well known Jewish practices related to the observance of Shabbat (the Sabbath) is the lighting of oil lamps or candles before its commencement.
In commemoration of the double portion of Manna (Exodus ch.16).
They're called Shabbat candles (Neirot Shabbat in Hebrew).
They're called Shabbat candles (in English); neirot Shabbat (in Hebrew); or Shabbes Licht (in Yiddish).
Showering, cooking, and setting up the candles.
Traditionally, the Shabbat candles are lit by women. If the woman is unmarried, she will usually light one candle, if she's married two and often one for each child.
You don't light more candles than usual. In the blessing over the candles, the Shabbat ismentioned first.In the event that a more frequent occasion coincides with one less frequent, the morefrequent is acknowledged and blessed first.
They're called Shabbat candles (Neirot Shabbat in Hebrew).
They prepare their children for Shabbat and light the Shabbat candles.
to honour the shabbat
The Shabbat is observed by all Jews, both men and women. However, it is the women who traditionally light the Shabbat-candles. See also the Related Links.Link: Why do women light the Shabbat candles?Link: Women and the lighting of the candles
They're called Shabbat candles (in English); neirot Shabbat (in Hebrew); or Shabbes Licht (in Yiddish).
The Shabbat is observed by all Jews, both men and women. However, it is the women who traditionally light the Shabbat-candles.See also:Women and the lighting of the candles
Candles used in Judaism usually don't have names, other than the names of the occasions they're used on, such as: Shabbat candles, used on Shabbat Havdalah candles, used on Havdalah Hanukkah candles, used on Hanukkah Yahrzeit candles, used for someone's Yahrzeit
No Orthodox or conservative Jews should put 13 candles in their window. The most candles they will put in the window is 11: Eight for chanukkah, 1 shamash and 2 shabbat candles. But Shabbat candles are not normally placed in windows. In some orthodox homes young girls light candles to copy their mothers (who are also lighting candles). This might explain why there could be 13 or more; but for Jewish purposes only 11 are necessary. The rest are extra.
At a shabbat service at your home or at a synogauge you may light the shabbat candles and say the shabbat blessings. Also some people follow it with hallah and/or a kiddush.
Showering, cooking, and setting up the candles.
Traditionally, the Shabbat candles are lit by women. If the woman is unmarried, she will usually light one candle, if she's married two and often one for each child.
You don't light more candles than usual. In the blessing over the candles, the Shabbat ismentioned first.In the event that a more frequent occasion coincides with one less frequent, the morefrequent is acknowledged and blessed first.