Invitro
An invitation intro: a demo or intro whose entire job is to advertise an upcoming demoparty.
The word squashes together invitation and intro. An invitro usually comes out a few months ahead of the party — ideally at another party, where the audience is already facing the big screen — and has to get across the date, the venue, which compos are planned and where to find out more. All of that has to fit between the effects.
It's a relative of the cracktro and the BBStro: code as advertising, where the advertising only works if the code is good enough to impress. Organisers often ask a well-known group to make one, since a strong invitro signals that the party takes itself seriously. A weak one signals roughly the opposite.