Concert item/ spot?

A concert is a single musical event.
A concert series is multiple musical events.

I want to know another thing. In a concert may take part musicians, singers, dancers... Let's imagine that each of them performs only one THING - a musical band performs a Single song, a dance crew - a dance...
But how do I name all these Single things, that are performed by a band\ singer\ musician?

It's called an act.

Oh, thank you very much!!=)

Roman DefinerLet's imagine that each of them performs only one THING - a musical band performs a Single song, a dance crew - a dance...But how do I name all these Single things, that are performed by a band\ singer\ musician?

There's also this:

The dance troupe performed two numbers at the concert.

Also 'routine', so you

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Also spot.

"A position or length of time in a show assigned to a specific performer". (Collins)

EDIT: I've just noticed that 'spot' appeared in your thread title.

Thank you for some more words!