For example in this sentence, do we need an article before comedy?
Improv is essentially [a] comedy.
For example in this sentence, do we need an article before comedy?
Improv is essentially [a] comedy.
Comedy can be used as a countable or uncountable noun. In the example sentence, we are probably using it as an uncountable noun, in which case the article should be omitted.
It depends on how you're describing Improv.
For example I would expect no article in this sentence:
Whose Line Is It Anyway? is essentially comedy with points.
Whereas I would in this one:
Shakespeare's A midsummer night's dream is a comedy.
As Jasper Loy point out, the distinction comes between countable and uncountable use.
In my first example comedy is not countable because it is used throughout the show, like you might use paint.
In the second example, there is only one play, so there is only one comedy.
'a comedy' would describe a specific show:
Friends is a comedy.
In terms of improv, I'd say:
Improv is essentially a style of comedy.
Because you can improvise without it being comedic.
We do not need an article since comedy is being used as an uncountable noun here. Another example of this usage is:
He dreams of having a career in stand-up comedy.
An example of its usage as a countable noun is:
Friends was a highly successful TV comedy.
The use of the adverb essentially may cause confusion. You could say:
Improv is comedy.
Improv is essentially comedy.