The Omer is counted from the second night of Pesach till the night before Shavuot, the feast of the harvest (Exodus 23:16). Since the holiday of Shavuot occurs in the season of Sivan (May-June) when the wheat begins to ripen it is called Hag ha- Katzir. It was from this wheat that the two loaves of bread were baked and brought to the temple as an offering, Shete Ha-Lehem, after which the new season’s wheat could be used for the Temple meals offerings. The counting of the 49 days (seven weeks) between the festivals of Pesach and Shavuot connects the exodus from Egypt with the festival of the receiving of the Torah. Just as one who awaits a most intimate friend on a certain day counts the days in eager anticipation, so do we count the days from our liberation till the day we receive the Torah, the culmination of our freedom. It is important to count the Omer at the beginning of the night, usually after the Maariv service.