It is the blessing over the occasion, said during any annual special occasion, not just the Passover seder.
אֱלֹהֵינוּ מֶלֶךְ הַעוֹלָם בָּרוּךְ אַתָּה יְיָ
Blessed are You, ADONAI our God, Ruler of the Universe,
Baruch atah Adonai Eloheinu melekh ha'olam
וְהִגִּיעָנוּ לַזְּמַן הַזֶּה שֶׁהֶחֱיָנוּ וְקִיְּמָנוּ
who has granted us life, sustained us and enabled us to reach this occasion.
shehecheyanu vekiyemanu vehigi'anu lazman hazeh.
It's not a prayer. In the Haggadah, which is used for the seder, there is the story of the Exodus which we read.
The word 'seder' is Hebrew for 'order'. The Jewish Seder is the ceremonial meal in Passover, during which, according to a set of ancient customs and text, we recount the Exodus from Egypt.
PASSOVER is the Jewish holiday celebrated unanimously with a Seder, which is an organized prayer, social interaction, and meal. In the Mizrahi Jewish Communities, there is often also a seder for Rosh Hashanah.
Mei melach (מי מלח)
Wrong. The seder is held at home, and the special festival prayer-services are held in the synagogue.
SEDER : Hebrew for "order", can aply to a prayer liturgy, or more commonly the Passover meal, or feast, celebrating the Hebrew holy day. CEDAR : a large coniferous tree having an aromatic resin in its wood, notably Cedrus libani or "cedar of Lebanon".
Salt Water at the Passover seder symbolizes the tears shed by the ancient Hebrew slaves.
It is set on the table during the Passover seder (the first and second nights of passover).
Generally it occurs only during Passover, a Jewish holiday. There is also a seder for the holiday of Tu Bishvat, but this seder is rarely observed.
during a passover seder.
The holiday of Passover officially begins on the evening of Monday, March 25th (in 2013). Most people who celebrate Passover will have a seder either on the 25th or the 26th.
night of passover