Today is the first of the two Rosh Chodesh ("Head of the Month") days for the month of Adar (when a month has 30 days, both the last day of the month and the first day of the following month serve as the following month's Rosh Chodesh).
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 29th Day; The Lunar Files
We were not placed here to do the possible. Let the heavenly beings bring cause into effect, potential into actual. He did not breathe from His innermost depths into flesh and blood to achieve the facile and the ordinary.
We are here to achieve the impossible. To teach the world tricks it feigns it cannot do. To fill it with light it does not know. To make the blind see, the deaf hear, the bitter sweet, the darkness shine. To make everyday business into mystic union. To rip away the façade of the world and to bring it to confess its secret oneness with the Divine.
When they tell you, “You can’t go on that path, it’s beyond you!”—grab that path as your destiny.