"It is not good for man to be alone" (Genesis 2:18). This observation, made by God regarding the first man in the book of Genesis, reflects the Jewish belief that, ideally, every man and every woman should find a partner and marry.
The Talmud maintains that 40 days before a child is conceived, a heavenly voice already declares whom they will one day marry. In the Yiddish language, the person a man is destined to marry is called a Bashert, meaning a "partner or soulmate to whom one is destined". The path to be taken in order to get married, as described in the Talmud, consists of two parts: betrothal or Kiddushin, followed by marriage or Nisuin. In the Talmud, the period between these two stages is 12 months. The first stage (Kiddushin) opens with a ceremony called Erusin, in which the members of the couple recognise themselves as bound to one another. During the following year, the couple prepares their home and prepares themselves for marriage. At the end of the year, during the Nisuin ceremony, the actual marriage takes place.
Although some couples continue to experience a period of engagement, today the stages of Kiddushin and Nisuin take place within the same wedding ceremony.
The wedding ceremony
It is common custom for the bride and groom not to meet during the week preceding the wedding. This makes the moment when the couple meets on the wedding day particularly romantic.
The bride wears a veil during the wedding. The rite in which the veil is placed on the bride (Bedeken) is traditionally celebrated shortly before the wedding: it is the groom himself who places the veil on his wife's head. The wedding ceremony requires the bride and groom to stand beneath a canopy supported by four poles (Chuppah). It is a symbol of the family that the couple will build and is often adorned with flowers. After several blessings over a cup of wine have been recited, the groom gives the ring to the bride and, slipping it onto her finger, recites the following formula: "Behold, you are sanctified to me according to the Law of Moses and Israel." The rabbi then reads the marriage contract (Ketubah). 
This document, written in Aramaic, makes clear the husband's obligations towards his wife both during the marriage and in the event of divorce. Dating back thousands of years, the formula of the contract has always been particularly important because of the guarantees assured to women. (…) After the reading of the Ketubah, another seven blessings for the future of the couple are recited and the wine is drunk.
It should be borne in mind that in the Jewish tradition, after the destruction of Jerusalem and the Temple, no celebration is without a touch of sadness. For this reason, the wedding rite also ends with the breaking of a glass, a sign that the world has not yet attained perfection. (…)
It is traditional, in the week following the wedding, for parties for the newlyweds to be organised in the homes of relatives and friends (Sheva berachot – seven blessings).
Source: "Per conoscere l'ebraismo" by Daniel Taub