When lighting the Chanukah lights, the entire household should gather so that the miracle which is being commemorated will be publicized. [Pirsum hanes, "publicizing the miracle," is an essential component of Chanukah.]
After lighting the first candle, and while lighting the others, one recites or sings HaNerot Halalu. When the lighting is concluded, Chanukah hymns are sung in accordance with local custom.
For your information, HaNerot Halalu is a Jewish prayer song.
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