The similarities between theater and performance arts:
Both involve a large audience
Is shown live to whole audience
Both are meant for entertainment
Those are just a few that I can think of. I'm sure you can find more.
A functional text is a text which helps us to do something such as cook a recipe, assemble a piece of furniture etc. The approach in learning from such text could be relying on headings and graphics to see what are the steps from the headings and the graphics to show us how to put things together with a picture for example.
