Kiddush is a blessing usually recited on Friday night and at Shabbat lunch (two different versions). Other versions are said on holiday eves and days.
The blessing is recited over wine (or grape juice). After the Kiddush is recited, everyone takes a sip of the drink.
Kiddush might be said at home or in the synagogue. Many families have a special Kiddush cup for this purpose.
Traditionally, only men recited Kiddush. Today, in many households men or women can recite Kiddush.
Kiddush can also refer to a reception and light meal in the synagogue after Shabbat or other holiday morning prayers.
In some communities, families might sponsor a Shabbat morning kiddush to mark a special occasion.
Text adapted from Simple English Wikipedia, Creative Commons Attribution-ShareAlike License 4.0.
Shabbat table setting by Crzrussian on Wikimedia Commons, CC BY-SA 3.0.