Milonga is a Tango Dance Party.
The pure joy of dancing tango is found at the Milonga.
What is a Tanda?
At a Milonga, music is played in sets called Tandas.
Usually three or four songs are played by the same orchestra followed by the ‘cortina‘ (the curtain) which signals the end of the Tanda. If you ask someone to dance and they accept, it is assumed that it will be for the entire Tanda.
Cortinas are an interesting little detail at a Milonga. A cortina is unique to each DJ. Some will select one cortina for an evening and some will use a different one for each Tanda.
Some are humorous; some are grating on the ears; some are simply beautiful music. In any case, the cortina is supposed to be a piece of music that people know not to dance to.
It’s your signal to smile, say thank you and (possibly) change partners.