On the first of Shevat in the year 2488 from creation, Moses convened the Jewish people and began the 37-day "review of the Torah" contained in the Book of Deuteronomy, which he concluded on the day of his passing on Adar 7 of that year.
Today is Rosh Chodesh (“Head of the Month”) for the month of Shevat.
Special portions are added to the daily prayers: Hallel (Psalms 113-118) is recited -- in its "partial" form -- following the Shacharit morning prayer, and the Yaaleh V'yavo prayer is added to the Amidah and to Grace After Meals; the additional Musaf prayer is said (when Rosh Chodesh is Shabbat, special additions are made to the Shabbat Musaf). Tachnun (confession of sins) and similar prayers are omitted.
Many have the custom to mark Rosh Chodesh with a festive meal and reduced work activity. The latter custom is prevalent amongst women, who have a special affinity with Rosh Chodesh -- the month being the feminine aspect of the Jewish Calendar.
Links:
The Jewish Month of Shevat
The Laws of Rosh Chodesh
How Does a Jewish Woman Celebrate Rosh Chodesh?
There is a quiet happiness: an inner sense of bliss, the innocent joy of a small child, one of wonderment and gratitude. It is a happiness to carry with you at all times.
Then there are those seasons when happiness blooms for all to see, bursting out in song, in dance, in celebration. A festival, a wedding, a time to feast and rejoice with family and friends.
But the ultimate happiness is the joy of Purim. It is no longer about you, your family, your life. It is about making others laugh, bringing smiles to the weary, celebration to those who feel abandoned, a feast to those who had lost all hope.
It is a season for breaking out of yourself, out of your character, out of all those bounds you have set for yourself—“beyond knowing.”
The light of Purim knows no bounds.