Haft Sîn (Persian: هفت سین) or the seven 'S's is a major tradition of Norouz, the traditional Iranian new year. The haft sin table includes seven items specificly starting with the letter S or Sîn (س in the Persian alphabet). The items symbolically correspond to seven creations and holy immortals protecting them. Originally called Haft Chin (هفت چین), the Haft Sin has evolved over time, but has kept its symbolism. Traditionally, families attempt to set as beautiful a Haft Sîn table as they can, as it is not only of traditional and spiritual value, but also noticed by visitors during Norouzi visitations and is a reflection of their good taste.

The Haft Sin items are:

1. sabzeh - wheat, barley or lentil sprouts growing in a dish - symbolizing rebirth
2. samanu - a sweet pudding made from wheat germ - symbolizing affluence
3. senjed - the dried fruit of the oleaster tree - symbolizing love
4. sîr - garlic - symbolizing medicine
5. sîb - apples - symbolizing beauty and health
6. somaq - sumac berries - symbolizing (the color of) sunrise
7. serkeh - vinegar - symbolizing age and patience


While traditionally incorrect, sometimes a missing Sin is exchanged with another item starting with an S. For example:

. sonbol - the fragrant hyacinth flower (the coming of spring)
. sekkeh - coins (prosperity and wealth)


Other items on the table may include:

traditional Iranian pastries such as baghlava, toot, naan-nokhodchi
dried nuts, berries and raisins (Aajeel)
lit candles (enlightenment and happiness)
a mirror

decorated eggs, sometimes one for each member of the family (fertility)
a bowl with goldfish (life, and the sign of Pisces which the sun is leaving)
a bowl of water with an orange in it (the earth floating in space)
rose water for its magical cleansing powers

the national colours, for a patriotic touch
the Quran
the Shahnama or the Divan of Hafez


Source: Wikipedia:Haft sin table"
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But we didn't mistakenly exchange Serkeh with Sekkeh, we did it because I don't like the smell of Serkeh (vinegar) ;)

By the way, I've put notes on all 7 Ss and other main parts of Haft Sin table.